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Summary

This session provides medical professionals with a comprehensive overview of Total Neoadjuvant Therapy (TNT), which combines chemotherapy with radiotherapy to reduce metastatic disease. Expert speakers will present on the benefits of TNT, its efficacy based on landmark clinical trials, and the importance of quality surgery. Attendees will gain the knowledge they need to make informed decisions about the best course of treatment for their patients.
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Description

The Dukes' Club 2023 educational weekend lectures

Sponsored by ETHICON - Exclusive primary sponsor for the Dukes' Club weekend!

First session Stepping outside the colon including:

  • TNT and rectal cancer by Rob Glynne-Jones
  • Reading MRI for rectal cancer by Tom Glover
  • Advanced Cancer MDT by Ian Jenkins, Rob Glyn Jones, and Tom Glover

Learning objectives

Learning Objectives: 1. Understand the principles of total neoadjuvant therapy and how it can help in oncology treatment. 2. Learn the differences between the Stockholm one trial, Rapido trial, French trial, and Prodigy trial with regards to rectal cancer treatment. 3. Comprehend the role of the surgeon in improving overall survival of rectal cancer patients. 4. Determine appropriate local and distant recurrence rates in curative rectal cancer treatment. 5. Develop an understanding of risk adaptive approaches when deciding to give chemotherapy or radiotherapy.
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Computer generated transcript

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The following transcript was generated automatically from the content and has not been checked or corrected manually.

Right. So, welcome to the session. Uh We have some excellent speakers today and I'm really grateful they are spending their staff here with us. Um Our first speaker is Doctor Robyn Jones who is an excellent oncologist. He's been uh part of the committee for the Guidance for the Rectal Cancer um oncology treatment. And um he's gonna be followed by uh to um who's gonna be the radiologist and finally gonna be speaking about some cases um with one of our surgeons. Um Thank you very much. Thank you so much for inviting me the last time I came to get talk to Duke's Club. Um You don't have those in ground opinions. You have lots of fresh ideas. I, I went away thinking about things for about four months. So thank you for inviting me. I'm going to talk about total neoadjuvant therapy and see if I can. So these are my disclosures. My other disclosure is everyone talks about me as being a radiation oncologist who doesn't like radiotherapy. And part of that is I do not think that my tribe, the radiation oncologists acknowledge how much late faith can affect a patient's life. Late faiths and radiotherapy. So I try and talk a little bit about who benefits because I think, I think that's the most important thing really, what we should be giving and kind of give you some framework for NDT decision making. I don't think you can get anything for exams here. But what I'd like to think is after this, you have a much better way of putting your case for surgery alone because I think there is still a strong case for a lot of patients to have surgery alone and not TNT. So as cancer physician, we're going to think about either overall survival, which is important or quality of life. And there are lots of things that impact on, on the quality of life. And we use the TNM staging, we use the MRI based anatomical features like the CRM, the extra renal rescue invasion, tumor deposits. And then we kind of get some idea of what the local recurrence rate might be if we do or don't give treatment and the local and the metastatic, which might happen if we don't give treatment. Um And that sort of risk adaptive way is how we kind of think or I, I think of giving chemotherapy or radiotherapy. So this used to be the traditional approach that um you looked at your MRI, you decided um whether the patient was high risk or not, you gave them some short course and then immediate surgery or gave them long course chemo, radiotherapy and then you operated, you looked at things under the microscope and then you gave them some chemotherapy and that worked pretty well really. But, um, the problem is that you still get quite a low apr, quite a high apr rate. Some institutions is, is lower. I mean, I think it's really interesting if you look at the, I was talking to, to Ian Jenkins just a minute ago that the, um, if you look at the trials, the Rapido and the, er, protege trial, the French trial, the French had twice, twice as many low rectal cancers as the rapido trial. But they had half as many APR s. So they, they're really pushing for, for restorative surgery and it probably accepting a lot of functional problems that the, that the Dutch probably don't do. So you get a very reasonably low PCR, perhaps about 14 15% if you just give chemo radiotherapy and perhaps less, if it's a short course, there's still a substantial metastasis rate 25 30%. Um, and more. So if, if it's a low rectal cancer and the problem is it's, it's difficult, even if you want to give chemotherapy, sometimes if you get a little bit of infection or some postoperative problems, it's difficult to get the chemotherapy in. So the TNT approach, either you have induction chemotherapy and the trials that have been effective have used Folfox II and I'll talk about that a bit more in the future um or treatment after short course with um FO fo or K and then you have again, good quality TME and some of the trials give further chemotherapy, further postoperative avant chemotherapy there. So the arguments are pretty good because it's a very pragmatic way if you give the treatment up front the patients. Well, there's no postoperative morbidity. So it's a very easy way of getting the doses in with full doses and, and, and, and good compliance. Um And to my mind, if, if you believe that there's a sort of um some immune effects from this, which I think there are partly, I think there are immune effects from oxaliplatin. But also if you are creating neo antigens, you've got all the machinery there to process the dendritic cells and to create memory cells. If you're giving things in the, in the preoperative setting, I never used to understand why before we looked at sort of immunotherapy, why recurrent rectal cancers always do so badly. They don't respond to radiotherapy terribly well, they don't respond to surgery terribly well, always. And they don't respond to, to chemotherapy terribly well. And that's because I think you don't have the machinery there, the immune machinery to, to assist you. So sorry. So total knee adjuvant therapy combines some chemotherapy. It doesn't define how much it is. So, it's a concept really. Um And the, the thing is that the, the radiation and the oncologists have got together in this one. And we've ganged up on you lot the surgeons because it suits us both. We can give radiotherapy and chemotherapy and then we get both reduction in metastatic disease. And we also get a, a fair few patients who don't need surgery. So the, the old joke, there are three principles of locally advanced rectal cancer, but everyone's forgotten what they are. That's the old joke. But actually, I think there's one that is still there, which is the quality of surgery is paramount and this is the paradox that your surgery is improved and continues to improve. But the radiation oncologist and the medical oncologists want to say, oh, let's avoid surgery. Um And I personally think we are actually giving too much TNT and there should be some patients having straight to surgery. So this is uh if you look on the left, going back to 1990 that's the Stockholm one trial sort of uh overall survival is just over 40%. And these are the rapid o trial. Overall survival is more like 80%. Ok. Now, there are lots of sort of caveats for that because um although in 1980 it was all comers, we didn't have very good scans to pick up um um metastatic disease. So there's probably a few patients there who had metastatic disease even though there are lots of dukes a patients. And on the right with um with, with Rapido because they, they're selected to be patients, 60% of the patients had a, a positive circumferential marginal MRI but they're rather younger. The average age is about 62. So there's, there, there are other things going on but you have, you, surgeons and your forebears have almost doubled the survival over 30 years. Ok. Our tribe has added a little bit to that, but not as much as, as you have. So, what is an acceptable rate of local recurrence now? 2023 what do you think? Anybody? What's an acceptable rate for your, you don't get measured in a ember cap? Anyone? Less than less than 5%? Any, any, any advances on less than 5%? Less than 10%? Ok. So what's an acceptable rate of distant metastases? Oh, that's not fair. I'm a surgeon. But if you have a positive margin, you will double the rate of metastases. So you are responsible and you've done that thing with improving survival from 40% to 8, 80%. So you are responsible. You don't think about that. Do you, do you as a surgeon? Think about that? Does it come into the MDT? Well, this patient's going to have a metastasis, high risk of metastasis. Which good chemotherapy. Yeah. No, the MVI maybe I don't think you, do. You think about that? I don't think you do a be it. So lots of studies, lots and lots of randomized phase two, phase three studies, doing all the things I would ignore things like the follow up trial because that's, that's said to be a locally advanced rectal cancer trial. But actually, it's, they're very early cancer patients and I don't think the surgery is that great park, the Chinese who are listening to this. So, and, and there's early rectal cancer ver prospect and there's a Chinese trial PS S on. So there's a lot of data there, I'm going to pick and choose a little bit. So these are the landmark trials. So up on the left, this is Rapido and down here prodigy MRI based for Rapido, it's difficult to see what the French, how they, if you look at the papers, it's quite difficult to see quite how they decided to give the radiation. Uh they're sort of t three T four Rapido short course chemotherapy and nothing afterwards. Prodigy full ox theory, you try giving full ox theory to someone over 70 if they're not performance status of one performance status. Naught. It's very difficult. It's a toxic regimen. I'm amazed that they didn't have any uh treatment related deaths. I've used Folfox the, I've had treatment related deaths. It's a toxic regimen even in performance status. No. So they gave three months of chemotherapy ox the and then adjuvant chemotherapy for three months afterwards, both of these trials achieved their primary endpoint with um disease related treatment. So, failure or DFS and they had a significant reduction in metastasis of 7%. So the, the trials did what it said on the tin, it reduced metastatic disease. So, and these are the curves D RTF at the top, distant metastases at the bottom, they go apart early, they stay apart. So it's a, it's a valid, both of those are quite valid and a doubling of the pathological complete response rate to, to 28%. So J is actually improved survival, I think with the overall survival about 55 or 6% better. Uh In it's, that's only a presentation. It's not been, it's not been published yet. But the uh mature data seems to suggest that has a an improvement in survival but rapido doesn't. So the main challenges I have with these is trying to interpret things when you've got a lot of patients who are performance status, naught and the average age is 62 average age in my clinic has been 72 and very few of the patients are actually performance status. Naught. Um So, and I I looking at the data, how do you pick who is actually going to benefit from this and who is not going to benefit? Um And who's going to lose from this? And I think that's, that's more of a question. So I was partly responsible for the ESO guidelines and what we did in the ESMO guidelines, we we were risk adaptive. So we had here low risk and these patients, they're not the low ones take out the low ones who are going to have an A, an A P or, or whatever, because they have a different sort of outcomes. But these are T three A B. So only up to five millimeters into your um muscularis propria. Uh We didn't care about whether they were node positive or not because we didn't think that that impacted anymore. If, if the nodes are positive and you're doing a TME, the nodes are in the bucket. If you're not doing a TME, they're still in the patient fine and negative external vascularization, negative CRM. So that was the low risk at the other end was high risk. These patients were unlikely to have a curative resection. If you just went to surgery, there were t fours, lateral lymph nodes, circumferential margins, positive involving limb, et cetera, et cetera. And then there's a group in the middle that you didn't need down staging. So we said these are early, these only need surgery. These are late, they probably need either chemo radiotherapy or TNT. And these you can decide in the middle. So that was fairly sort of straightforward and it was based on the fact that um we, we had some trials to, to, to, to show that. So if we take the late ones, the the the the high risk ones, um those should benefit from the TNT, but it's rather difficult because if you look at these, if you look at the intended curative resections in rapido and prodigy, they're no different really. The R no resections are identical in rapido 95 versus 94% in protege. And the local recurrence similar in protege, the original paper was slightly higher but non, significantly. And as time has gone on, that's significantly worse, local recurrence for TNT in rapido, significantly worse local recurrence. So you said that the local recurrence rate should be less than 10% or less than 5%. So the local recurrence rate there is 10%. So, what about the quality of surgery? Surely if you shrink things down, it's going to make your surgery easier, isn't it? It's not going to make it easier. Well, rapido assessed by the surgeon. I think that the Germans have shown that when you assess the, um, the quality of the surgery, maybe you overestimate the quality of the surgery a bit. I certainly would if I was a surgeon. Um, so, um, but if anything, they numerically better for the patients who just had the straightforward chemo radiotherapy rather than TNT and in protege that was assessed by the pathologist, looking at whether it's in the mesorectum plane. And again, it looks slightly better if you had the standard chemo radiotherapy, not significant but slightly better. So, I don't think it's necessarily making your surgery easier. It's probably making your surgery more difficult. So, what is the additional value of chemotherapy for those bad ones? Well, it doesn't make it easier it's not improving the quality of your surgery. It's not helping an a no resection. It's not reducing local recurrence, but it's dealing with fewer metastases. And that's what I think you need to say. These patients probably have a much higher rate of metastatic disease with ural vascular invasion and with a CRM threatened. So, but do they really benefit more? So if you look, sorry, you won't be able to see that. But those are the, the forest plots for those two trials, you could do a forest plot to Stella. But since it wasn't a positive trial, that doesn't mean anything. So I don't know if you can see. But all of the features there are all slightly to the left of unity. So they all seem to say there's some benefit, all those features t stage end stage, extramural vascular invasion. All these sort of things seem to say it's slightly better. Uh if you have chemotherapy as well as chemo radiation, but the only factors that actually don't touch unity or don't cross unity, the only factors that you could think really are important are young age, good performance status. T three T two T three on, on MRI no positivity. CVS, no involvement of the lateral lymph nodes, no MVI or lymphoma involvement and a low C A. Now, in my book, those are good prognostic features. They're not bad prognostic features. And it's interesting that the smaller tumors seem to have been doubling their PCR rate. So maybe you've got a group of patients that are in between. Maybe it's not the really bad patients, maybe it's not, maybe it's the, the intermediate ones who are doing some of the, the most benefit there. So, going back to this one, the, the what we call the low risk patients, not low rectal cancer, the ones in the mid and upper who are T three A B. We go back to those. We based that partly on the mercury study, which showed that the local recurrence rate for those with surgery alone was about 3%. Um albeit in extremely good surgical centers and the metastasis rate was about 12%. And at the time, we had some early data from o which was a German study based on MRI, um which was again selecting patients for surgery alone and their local recurrence rate was at the time 2.2% and 15% metastases. So we felt in deciding to recommend surgery alone for the low risk that that was a reasonable option. So, oum what they did was they said anyone had a circumferential margin that was threatened or a T four tumor. Uh then they had to have chemo radiotherapy or if you were in the low rectum, you had to have chemo radiotherapy. So kind of similar. Um But they didn't mention EMV, I don't think that was really being called in those days. So that was their scam and those, those had chemo radiotherapy, everybody else. No positive, et cetera had, um, surgery alone. And in the upfront surgery, they did have a few patients that they'd miss called. So about 4.7% had a positive margin, but only about a third of the patients were node positive. Uh, and the APR rate was 4.5%. Again, not the low rectal cancers. So the APR rate was only 4.5%. Uh And about a third of the patients got adjuvant treatment afterwards. So these are the, the top results are the ones with chemo radiotherapy. Obviously, you selected out a worse group and so they do worse. But the uh the final results published this year's local recurrence rate, 2.9% and 15.9% metastatic distant metastases. So that's, that's recent data. So if you take those, there's a, there's a another retrospective trial from China again showing uh surgery alone for this group of patients, which is very similar uh is 2% and five year D FS 88%. So about 12% metastatic rate again. And there's a Chinese trial that was stopped because it uh went beyond the, the, the recommended things stopped by the which was surgery lo versus chemo radiotherapy and uh chemo and a couple of cycles of chemo. And that was stopped because uh it, they actually had a, a worse local recurrence rate. 4% versus naught percent if you had chemo radiotherapy plus chemotherapy. So all these things are pretty similar. So here you are, you are all young. You have a resectable mid or upper rectal cancer, ok? If you have surgery, you have a 2 to 3% local recurrence rate, 15% chance of metastatic disease. Apr rate of maybe 4% and no benefit in overall survival. If you have chemotherapy or radiotherapy, I mean, if you're going to have chemotherapy and you have a hazard ratio of nought to 0.8 you're gonna make 0.3 of a percent impact on your local recurrence rate and maybe 2% on your metastatic rate for 36 weeks of treatment. Six or eight weeks to recover. You won't be able to work for a year. How would you, how do you cope if you won't work for a year? How's your mortgage going to go? You lose fertility? Did you have chemotherapy and radiotherapy? It's a big, it's a big, if, I mean, think about that when you're in your MDT, would you yourself really have total neoadjuvant therapy for the ba for the gains there for low regrettable cancer? Because, you know, I don't think you're going to improve your oncological outcomes. And uh the prospect study, this is pretty well the same group of patients who they randomized between radiotherapy and chemotherapy because they wanted, they did a non inferiority trial to see if uh if they were the same because they wanted to avoid radiotherapy but still give chemotherapy in this group. So if you had a, if you had a worse than 20 if you didn't have at least 20% response rate, you got chemo radiotherapy. But otherwise if you had uh a good response to chemotherapy, you went straight to surgery and the other arm was chemo radiation surgery. And then chemotherapy. I think it, one thing to remember in the United States is that about 80% of all patients in both arms got further chemotherapy afterwards. So their, their inclusion criteria is very similar except that T two and T three, they didn't want T fours or N two. In those, they excluded the bad boys. They wanted a crm of at least three millimeters as inclusion. So that's almost certainly going to make the patients T three A T three B, very few patients more advanced than that. They had to be a candidate for sphincter sparing. So they again avoided the low rectal cancers. So again, the low risk group that ESMO would say and that they decided that they needed chemo radiation. It doesn't actually say what the, what the, the rationale for needing chemo radiation was. So they're all similar to ESMO, except there were a few of the patients that had a, a low rectal cancer and there's no detail there of extra renal vascular or uh tumor deposits. So the top curves are the inferiority margin which overlie one So it's non inferiority. So you have, and the bottom one is DFS, which is pretty similar, um, there as well. So, to me, the APR rate was 2% versus 2.4%. I mean, these, to me, these patients didn't need either chemotherapy or radiotherapy. So it's an, it's, it's an equivalent trial. It's equivalence trial, but I don't think they needed either of those. So again, what about the, those patients there did not go into watch and wait, they had to have surgery. So, are you going to want chemo radiotherapy for a watch and wait? So you might have, if you're in the upper or mid rectal cancer, you're going to have a, you should have a sphincter sparing operation because only about 4% of you are not. Um, and you might have a 50% chance of avoiding immediate anterior section, but you're going to have probably a third of those will have a regrowth. And if you have a regrowth, you probably will do worse, probably worse function if you have both chemo radiotherapy and surgery than you would have if you'd had surgery alone. Rodrigo Perez does not do, uh, watch and wait in patients that you can't feel with the fingers. They're above seven centimeters. They don't because they don't believe in, in that. So, if you're in the early rectal cancer group, are you going to want to have chemo radiotherapy and chemotherapy to avoid having surgery? Some people will and I accept that some people will, but I don't think all people would accept the downside of that. Sorry. So the problem is who, who's going to benefit and who's going to be a loser. And you're thinking about different things. You're thinking about metastatic disease, local recurrence and avoiding radical surgery. So there are different aims and the patient is gonna have different aims too. The patient will prioritize those differently. So I think one caveat I would put here is, you know, the trials that we've done which show a benefit is full oxy. And then chemo radiotherapy, there is no trial which shows a benefit from full fo or K pox and chemo radiation. The trial hasn't been done and there is no trial that shows chemo radiotherapy followed by chemo K pox. Things improves your D FS and reduces metastatic disease. The trial is short course and chemotherapy. So just to point that out because everyone I see in the UK uses full fo or K po and then chemo radiation. So if you're going to advise TNT in your, in your NDT, is there any necessary criteria that's absolutely, absolutely not sufficient but necessary? Well, the only necessary is that you have chemo you have metastatic disease and those patients were excluded from the trials. So I don't think there is any necessary condition where you should advise. So how are you going to do it? Well, you can do it the USA way. The USA way is national guidelines. There do not distinguish low, middle and upper rectal cancer at all. And everybody with a rectal. Basically, if you got rectal cancer in the US, you get total neoadjuvant therapy. Despite those things, I've shown you about low risk to my mind. This is over treatment for a large proportion of patients. It's not the most cost effective if you've got a, a system. But then a fee paying system is automatically going to be somewhat um in inflationary and it doesn't tally me with what we're all trying to do. It just personal. I mentioned tailoring the treatment to the individual patient, which is why we do the MRI S and talk to the patient first. You can have strategy too, which is very rational. So if you're in an MDT, where you look at your MRI and you say this patient's got extramural vascular invasion, this patient's got tumor deposits, this patient's got a uh lateral pelvic lymph node. We're going to give this patient adjuvant chemotherapy anyway, no matter what the outcome is, if they have a complete clinical response, we're going to give them chemotherapy if they have a, a resection anterior section and uh they have a PCR, we're still going to say it was extramural vascular invasion and we're going to give them chemotherapy. Well, if your NDT does that, it's perfectly rational. I think you're a pessimist mind you, but it's, it's perfectly rational to say, well, let's give the patient TNT up front. It's a kind of belt and braces for, uh, for the uh TN for watch and wait as well. Or there's the third way, which is the risk adaptive way, which you're aware of the risk of local recurrence. You're aware of the risks of uh metastatic disease and you make your decisions on the basis of the quality of surgery that you see is being done and you know, is being done. And I think you also have to tailor that to the patient's goals because there are some patients as we all know that, say you, I'm going to have a stoma over my dead body and, and you know, there is no persuading those patients that they're going to have a stoma, they, they will die without having a stoma. So I think to have an informed patient discussion which should integrate with your MDT. You need the patient's health status, comorbidities, performance status, but you also need to know the current values, the current values and goals and preferences of the patient. And I think to me that is really important and the problem I have with some of the MDT S is sometimes only one of the nurses has seen the patient when we're discussing it. And I feel, you know, we here we are discussing this, we know nothing really about the patient's goals and preferences. What is the likelihood of a patient requiring a, a permanent colostomy or a temporary ileostomy, avoiding TME surgery with non operative management. The risks of over treatment and under treatment, we need, you know, my tribe needs to take, take a patient and say, ok, there are risks if we undertreat you, there are risks if we over treat you. Ok. But you need to know those risks in order for you to make an informed decision, you need to know those risks. So I think frequency and types of assessment, I mean, you, you, you can't, if, if you're going to sort of follow a patient and pick up a regrowth early without it causing problems in the future, you need to have a very fixed regimen there and some patients are unwilling to do that and the risks of local and distant recurrence. I mean, there's no doubt that the opera trial shows that there are quite a lot of patients that you do not salvage with a regrowth. So I think it's all going to get so much easier in the future because I think the microbiome is coming along down the track and I think you're going to have much more pre pre habilitation and I think you're going to be manipulating the microbiome. So that, I mean, we have, we have lots of things like in uh Melanoma where you can give a patient a a microbiome transplant patients who are not responsive to immunotherapy will respond to immunotherapy after having a a transplant from a patient who was responsive. So I think you're going to have much more um ways of manipulating the, the patient's uh microbiome and their what for want of a word. Some people call the second brain in the, the neuronal tissue in your gut metabolic analysis. We there are chemotherapies that we can, we can test the with um metabolic processes one week into giving the chemotherapy and tell you this isn't going to work. And I think we need to further that up. But I think that is uh that is the future we will be able to tell within I think a week the metabolic processes that, that, that dictate resistance better radios to tell you the trajectory and serial CT DN to tell you the trajectory as well. So I think within five or 10 years, you're going to be looking at that you're not going to be sitting in an MDT and saying, oh, well, the MRI shows this uh and some extra ural Vastic invasion and let's give the patient a total neoadjuvant therapy. So, thank you for listening. OK. Thank you so much for such informative and promoting talk. Any questions moving forward. So fight your corner for surgery alone. I think that's important. Any questions bring the mic to you? Yeah. Yeah. Thank you very much. All right. OK. Thank you very much for the talk. I was just wanted to ask. So I've worked in different centers where there'll be some centers where you'll have a sort of t three resectable tumor with positive lymph nodes and the lymph nodes aren't encroaching on the CRM. But the units will always give neoadjuvant treatment before resection. And then other units where they wouldn't, they wouldn't ever do that. They would go straight to surgery. And I was just wondering why, why there's a, why this variation does, why this variation does this variation is, Yeah, because stick up your hands. Those of you in your MDT, where you see the quality photographs of the quality of the mes rectal excision. You sometimes see that in Barnet. OK. Not always, but sometimes we'd see that in Barnet. But the problem is there are still units that are not doing good quality mesorectum excisions. If you don't do a good quality mes rectal excision, you leave the lymph nodes in the patient full stop. So you, you, if you are, you don't need, I don't think you need chemotherapy. You can decide afterwards because you the, the the accuracy is not is, is still I have a radiologist, but I, I think the accuracy is probably about 60%. It's not, it's not perfect for when you say this is a no positive. Any more questions. More question got you on you. Um I think you um looking through the trials and their selection criteria, they usually tend to have very strict criteria about which patient is going to go on those trials. Yes. And sometimes, or through we talk, I understand that that does not reflect the reality at all, but still decision of those trials. What's your thoughts on that? Well, I, I think the, the rapid ou trial, you can't argue with the Rapido trial. They said we did an MRI 60% of the patients had a threatened margin. I don't think you can, you can argue there. But the, the prote day trial, it just says the T three T four and the MDT decided they needed chemo radiation. Well, that's a pretty vague kind of thing. You don't know why they said you needed chemo radiation a bit like the prospect trial just said they needed chemo radiation. So someone has said, I think this patient needs chemo radiation. But I, but you know, when we look at the things on the forest plot, it is very difficult to define a group that actually benefits in terms of, is this the group that actually reduce the metastatic disease in and they're all early features. So maybe it's, it's, you know, the, the, the same small, slightly aggressive cancers that actually are going to respond very nicely and get non operative management. The small T two T three A's, you know, you, you have a high complete clinical response rate from them. Maybe they're the ones that are benefiting in the, in the, in the metastatic setting too. But we don't know. Thank you. And my can I have one more question, please? Um, in your opinion, what would be the, maybe the five factors that we need to have in our current mds after all of this? Yes, the radiology, the oncologist. But what else we need to be discussing about? Well, I, I really think you, you, yeah, if, if I was to, if I was to sort of change the world, I would have a system where you went to the patient and you say here we have survival, local recurrence, non operative management, having a stoma, having good function, being able to have sex. Da da da da dah. How do you know which of the, which is the most important one? What's the next most important one? You know, and going down there? Because some people say, I mean, if you, if you ask those sort of questions to some elderly patients, you, you get really weird when you weird dances. I said to an elderly patient. So, what are your best hopes? You've got, you've got rectal cancer. What, what are your best hopes from? You know, you've got rectal from seeing me today. And the chap says, well, my wife's dying, I'm 82. She's dying. I want her to die at home. I just want you to give me something that's going to damp things down for three months so that she doesn't have to go into hospital. I don't care what you do, but I'm not having treatment until she dies. So you can say, ok, maybe we just give you five actions of radiotherapy damp it down for a while. You know, we can do that as an outpatient and you'd be still be able to look after your wife. But I think we need the patient's goals and preferences in a, in a much more formal way. Thank you. Do I to join you? Ok. And our next speaker um is Doctor Tom, he's one of the um radiologists. And um I'd like to say an answer him because he um what he's in v to and hoping that's not going to happen while he was giving me his talk. Thank you. Not that it's the one on the bottom. Right. Hello. Yeah, just while that's loading. Um Just to go on record MRI for nodes is absolutely rubbish as I'm sure he knew. Yeah. Right. So my name is Tom Glover. I'm a consultant radiologist at Saint Mark's Hospital. Thanks very much for the invitation to be here today. Um And I'm going to talk to you for the next sort of 2025 minutes about uh rectal MRI and interpretation and give you some uh pointers on that. Yeah. So just to go over the contents, I'm going to go through sort of an orientation thing like sequences. Um then anatomy, um morphology of tumors, sort of what to look out for to know what's what the radiologist is really looking for. But it's good for you to have an appreciation on as well and then a bit about staging and also tumor regression grade um as a final note. So, with regards to um the, the sequences that we use, we use um three sort of standard T two sequences. So T two is fluid bright and we do it in three planes. So axial coronal and sagittal um and the key thing really is that the um images need to be acquired um per particular and um parallel to the tumor in order to allow us um to assess particularly transmural uh extension and sort of mitigate partial volume, which may lead us to overall um transmit extension, for example. Um Then we also do a large field of view T two sequence and that gives us an overview of the pelvis. Um And it allows us to look for things like peritoneal deposits. Um and then inguinal nodes proximal or high IMA nodes as well. And it's a box we give Buscopan um as part of the um study. And that's once the localize has been acquired cause it's short acting. And that kind of helps to reduce artifact from peristalsis of the bowel, the sequences that we see often performed um elsewhere. So, not so much uh some marks diffusion weighted sequences which you've probably come across, which can be relatively helpful for assessing sort of initial tumor staging. Um But there's a lot of usage in sort of post treatment imaging, which is actually not validated uh partly because of it's poor resolution. Um T one sequence is also sometimes performed so fluid da sequences. Um They're not that helpful generally. Um Similarly post contrast sequence are also not particularly helpful. We also do um a 3d volumetric space sequence which allows us to kind of manipulate the planes a little bit has a bit more noise. Um But it can be helpful when the sort of standard sequences are not uh sort of don't give us the full picture. So here's just an example of a really nice quality MRI I wish all of them were like that. Um And you can see the crisp sort of definition of the um of the structure. So we can see a mid rectal polypoid lesion here, we can see bladder prostate sacrum at the back and the sagittal view. And then we've got a really nice axial through that where we can see the detail of the mural layers and the polypoid lesion. So that's kind of the ideal plane that this was acquired in. So that's kind of a modified ale it's not axial relative to the patient, like say a CT would be acquired. Um but it's very much requires the sort of radiographers to be switched on and identifying the tumor and also um making sure that the, the perpendicular and parallel as I described, sometimes it looks like that. Um Yeah, good luck. Planning anything off that this patient actually had an operation at Saint Mark's a few weeks ago. So we had to kind of use multiple MRI scans and CT just to make sure that we uh um did a good resection. It was all not in the end, so it's all good. But that this kind of thing annoys me when I'm trying to look at this in the MDT, of course. So this is the surgeon's view, at least that's what my surgical colleagues tell me. And I think that's a good view because it gives you a nice overview of sort of what's going on in the pelvis. Um And just gives you a broad sort of idea of what you're sort of tackling as an initial gambit and this on the left side of the image um of the screen, sorry, kind of just divided it into sort of low, mid and upper rectum. So low is sort of typically saying within six centimeters of the anal verge and then mid rectum sort of north of that up to the level of the anterior peritoneal reflection. That's approximately at this level on this particular patient in females. It can be very variable in males. It's usually at the top of the sentinel vesicles or thereabouts and then the border of the upper rectum and the sigmoid, which I'll come onto in a sec which um can be quite challenging to identify just a few of the anatomical bits on this um sagittal sequence we can see here this green arrow. This is the puborectalis um which we're looking for to help define the um anorectal junction. You can also actually see the submucosa bright here, which is just transitioning into internal anal sphincter at this level. And actually in this patient, the um pu coccygeal line, which we use as a sort of arbitrary marker of pelvic floor is at the same sort of level of the pubic rectal. Again, not always the case, this red line is the levator sort of posteriorly there. So I mentioned with regards to sort of the um trying to distinguish between sigmoid and the rectum because it has obvious implications on uh treatment strategies. And basically, because everyone has a slightly different length rectum, um you can't really get away with using sort of arbitrary length as has sort of traditionally been the case. So there's this concept of sigmoid take off where we're kind of looking for this little arcade of uh vessels coming off the IMA supplying the distal sigmoid. Hopefully you can sort of just appreciate that it's a little bit small on this diagram. And then on the right side of these images, um we can see the superior rectal artery coming to supply the rectum. So that's kind of what we're doing to try and make an assessment of whether we're sort of in distal sigmoid or rectum. OK. So a little bit more about the rectal anatomy um basics. So this is hopefully, you recognize is the um this green hash line is the axial plane of the, the crm that TME plane that you'll be dissecting in. And the sagittal here shows it posterior, we track them along the back of the sacrum from the sacrum, pire um and anterior sort of against the de no viers factor of the back here on this example. And just at the top of the seminal vesicles, we've got the anterior peritoneal reflection. OK. So as we've said, CRM is defined by um the mes rectal fascia. It's actually really defined by the TME plane that you're going to dissect in. Um and it extends down to intercity plane um pitfall that sometimes even as radiologists we come across. So you look at the tumor and it's extending anterior and it's a relatively high tumor. Um And actually, and that's called CRM involvement, but it's important to remember that. And once you get to the sort of peritonealized aspect of the upper rectum, you're actually just T four A disease. The CRM is actually technically not involved. What are we saying is involvement or anything really less than one millimeter involved, 1 to 2 millimeters may be a little bit more threatened. And then you're sort of talking about potentially going into a neoadjuvant uh strategy. Of course, CRM involvement associated with high local recurrence and worse overall survival. This just shows that anatomy in a slightly in a slightly different way. But again, you can see on the left of the screen, you've got the sagittal image of the rectum showing upper middle and lower. And then the sort of corresponding axial slices um with oops sorry with the predominantly peritonealized anterior part of the rectum of the upper um part. So just a little bit about pelvic musculature as well. Um As we can see here, we've got the um obturator internus here on the left of the pelvic side or this is a slightly, but it's a low cut axial cut. And then we've got the fibers of the levator which are fanning in from the right um there. And then this is slightly higher up. We've got our uterus in the middle, small bowel loops anteriorly. And then we've got a piriformis muscle as well here that we can see. Ok. So just to point those out. And then of course, we get down to the low rectum where the musculature is very important. So we can see here on the left side, we've got our levator on both sides, our anal rectal junction, which is marked by the puborectalis and the green arrow across here and the, the white hash line being the inter sphincteric plane and the external sphincter, anal sphincter and marked by the red bracket. And then we're really, this is kind of the best plane to use when you're looking at low rectal tumors. Um So we've got also sort of yellow star here, which will be uh sort of just over a centimeter, let's say from the puborectalis sling. So that would have an anterior resection uh TME dissection. This red star is sort of transmural spread, which is involving the adjacent leva. So you'd be pushed into an ela blue star sort of contained within the rectum, no involvement of the adjacent inter sphincteric plane. You might consider doing an ultra low um anastomosis color anal anastomosis, but dentate. And then if you're lower than that and still within the anal canal, so extending in you might do an inter sphincteric apr. So just to show you the rectal layers before we go on to the staging. So this is um not how all of the all rectums look as you'll have probably appreciated from the previous images I've shown. But here this is actually probably a post treatment rectum and you can see the layers quite nicely. So we've got the red arrow which is denoting the muscularis mucosa here and then a relatively chunky submucosa highlighted by the blue arrow. And one of the key features I wanted to kind of highlight is that you can see that there's all this kind of signal or heterogeneity within the submucosa, which is the normal sort of submucosal vessels. That's a particularly important thing when thinking about post treatment, imaging and trying to identify whether there's still residual tumor or whether you're restoring the architecture of the wall of the rectum. And then this is the this green arrow is the circular muscle of the muscularis propria. And the purple arrow is the uh longitudinal muscle. Often you can't really distinguish them together, uh separate them from one another. Sorry. But in this particular case, this is far between them. So we can see them quite nicely. And an additional feature with regards to the muscularis propria or the longitudinal muscle on the MRI is that um the longitudinal muscle can look quite irregular. So that can cause confusion at times when we are trying to assess for transmural extension. So when you're actually looking at a tumor, the morphology is really important. OK. So um obviously, you can have a different number of different morphology. So when you've got a circumferential near circumferential hemmer or polypoid lesions, um actually the sort of near near circumferential or semir lesions um are the sort of easiest in a sense to try and figure out where the invasive edge is because you can, you've got clearly identifiable um parts of the tumor. So if I point you at this um diagram up here on, at the top, we can see the white asterisks are at the wrong edges and those are the least invasive parts of the lesion. So that's what I'm looking for first when I'm looking at this MRI. Um And then I'm looking at the sort of opposite edge to look for where the leading edge is. So here, I've got rolled edges at about two o'clock and five o'clock. And we can see that the leading edge is extending from about eight or 12 o'clock. And we can see that I can't see any muscularis mucosa propria at that point. So there's definitely transmural extension and we can just see that the prostate is just anterior here. So we've got tumor that's actually abutting the prostatic capsule that's on vi fascia. So about mid gland level, it's also threatening the adjacent levator probably involving actually. Now, as I was saying before, regarding partial volume, we need to make sure that we can see transmural extension in at least two planes to call it. Um Otherwise, it might be an over call. Um And one other thing I wanted to mention with regards to tumor morphology and polypoid lesions. So we've in the bottom right here, we can see a low signal stalk which is partly replaced by this red arrow. Um But that's kind of the direction of travel of the invading tumor cells. So we can be relatively confident, at least from a macroscopic level that if that signal is preserved within the stalk, then it's a relatively early lesion still. Yeah. So just to go through the staging, uh we got early lesions on T one and T two. So T one lesions, we typically sort of talking about SM 12 and three. It's very difficult to identify SM one on an MRI, it's actually pretty hard for SM two and SM three unless you've got a really good quality study, um, which only Gina Brown seems to be able to do. Um, but I fully sort of get on board with that. So here you can see, um, here you can see that the submucosa sort of high signal as denoted by the orange arrow. So if it was, if that was preserved through the base of this lesion, then you could, it would be reasonable to call that SM two SM three. You can see there's a little nodule of tumor there which is extending through the submucosal layer and full thickness. Um T two would be sort of invasion into the adjacent muscularis propria that can also be better assessed or assessed in a different way with the rectal ultrasound, which has a higher uh resolution. OK. So in terms of T three tumors where we've talked about the morphology, so hopefully, you can appreciate here that we've got a tumor with rolled edges at approximately eight o'clock and 11 o'clock. And then we're looking at the opposite side for our leading edge. And as we can see here, there's all this mural irregularity, which is a transmural extension T three disease into the fat. And that's the adjacent lata which is threatened. And we can measure the distance of transmural extension sort of up to five millimeters being deemed sort of low risk, anything more than five or CRM positive. And of course, T four disease is high risk disease and that just highlights that tumor in the levator a little bit more nicely. T four disease. Um We have sort of two types T four A T four B. So T four A is relating to the peritoneum that what I've touched on already. So on the left side of the screen, this is just the select axial slice, but hopefully, you can appreciate this sort of seal appearance, which is uh sort of the sign we look for at the level of the anterior peritoneal reflection. And we can see that there's tumor which is extending through the wall of the rectum and contacting that. So it's either directly involving all sort of a butting. So T three slash T four A and on the right hand side, we've got a massive tumor extending out through the anal verge occupying most of the rectum. This is where the prostate is supposed to be. And you can see this tumor that's just invading quite significantly into the prostate and the base of the penis down here also sort of into the base of the urinary bladder. So with regards to nodal involvement on imaging, so just coming back to what's been touched on already, I think we're generally really quite bad at deciding whether there's nodal involvement or not and it's um sometimes it's really obvious. So the things we're kind of looking for are rounded morphology on the left of the screen there, um which is uh still a fairly soft sign, I would say um and heterogenous signal within the node. So hopefully, you can just about appreciate that that's not all the same kind of color. And there's a little bit of high higher signal and disruption of the capsule there. On that particular image, we're looking for obvious extra capsular spread. So here we've got a node nodal metastasis and it's all just irregular, horrible. So we just treat that really as a tumor deposit. Actually having a um tumor completely replacing a node is actually relatively rare. We can also use things like pet to look for avidity to give us a clue as to whether they're involved and people measure the size of lymph nodes that's kind of obvious. But I think people sometimes get carried away with size, sorry. And actually a large number of metastatic lymph nodes are less than five millimeters. So kind of good luck to identifying which ones actually involved. Um But as I've said in, in in recent years, it's kind of a combination of everything. So when do we need to worry about nodes? Well, there's emerging data that nodes that are even involved don't significantly affect the prognosis of rectal tumors. Sometimes their involvement is obvious. Um But which ones do we kind of care about in the MDT? So it's those that are involving the CRM. So particularly those that have extra capsula spread and have obvious tumor in them. If they're in involved in the CRM, then we need to take those seriously. Um, if they're encapsulated on MRI, but they're abutting the CRM, that's a different story. And that, that can be quite a nuanced discussion about whether to go down a neo adjuvant route or whether to perhaps just take a little divot around um of extra sort of fascia around it when you go straight to surgery and then side wall involvement as well, which is a whole different scenario which I'm not going to cover today. And then just to show you embi extranodal tumor deposits, when we call the MVI, we kind of have to be sure it's quite easy to overall. Um but EVI is actual tumor within the vessel, either expanding it or causing irregularity. And hopefully, you can see with this diagram on the right, we can see this large mucinous rectal tumor and this long term of um mucin tissue within the vessel, which is extending cranially along the superior rectal vessels. Um B MBI is kind of bad news, relatively speaking, predict of local recurrence, distant metastases and poor survival, extranodal tumor deposits is also something that doesn't really get um acknowledged so much um in sort of TNM classifications. But again, they're associated with quite a poor prognosis, but that's kind of tumor away from the, the main tumor. Um But it's not obviously expanding a vessel and we could try and be clever by saying, you know, is this tumor going within an internal iliac branch, is it going in a superior rectal vessel? Um and kind of try and determine or give a guess as to where there might be a likelihood of uh metastases of internal iliac draining into systemic circulation, getting sort of lung mets and vice versa, disease going into superior rectal vein, um causing liver mets from the portal circulation. And at the moment, there's a trial called the Serena trial done by Professor Gina Brown, um which is looking at sort of doing liver MRI for the high risk patients with EVI to see whether there's any real early detection of uh uh liver metastasis and just a quick final word really on um Mr tumor regression grade. So it's validated obviously histologically, but the MRI uh TRG is not, hasn't really managed to keep up. So it kind of sounds like a nice idea. Um And it's sort of split as you can see, um sort of 1 to 55 being no response, four, predominantly still tumor left and then sort of two and three are sort of combination of fibro and tumor or just fibrosis and no obvious tumor and one is kind of no obvious, well, no tumor. And you can't even see where the treated tumor was because that was such a good response. But at the moment, there isn't sufficient evidence for us to kind of use that to alter treatment decisions. Um But the sort of hope is that maybe it might be able to be used as a tool to kind of help select who would be potentially suitable for watch and wait, but obviously quite a complex scenario. Um and the trigger trial again done by Professor Gina Brown is in progress um trying to kind of iron out some of those questions. So take on points, I think when you're operating on these patients, obviously, you're looking at the reports, but it's good to kind of have a little play with the images and have a look to see whether you can make your own assessment and sort of build that up, the more you see, the more comfortable you'll be and actually the more you'll be able to uh sort of contribute in M DTs as well. Um And you know, it's, it's quite often our s your colleague who will kind of say, oh, what do you think about that bit or you know, is that really involved, et cetera? Uh use the sagittal image or surgeon for you to start with um look at your axial for sort of tumor morphology and transmural extension and looking at your rolled edges and the invading edges where you can sort of in the non circumferential tumors. And then just remember that the CRM is sort of the non periton at the surface of the rectum. And, and on that, on that note. That's all I've got to say at that point. I'm happy to take any questions. Yeah. Other questions. It turn silent. Ok. Too. Very exciting. Um Thanks very much for the talk. I'm just interested on at what point you request a repeat MRI for those ones that just look a mess. And how do you prevent in your institution getting scans that essentially aren't gonna help you with any form of diagnosis or planning? Yeah. So, thanks. I mean, in the first instance, I've shown you a sort of extreme example of that one that was just a blur gram and we definitely get a repeat. Sometimes it's a little bit more nuanced and there's only a little bit of artifact and it's away from sort of the main decision making area on the scan. Um But if it's a critical sort of decision point, like, for example, we had one a few weeks ago, which was a sort of partial prostatectomy and Ella in an elderly gentleman that didn't want a TP and the MRI sequences weren't quite right. The, the um, planes weren't quite right to make that call. So we recalled him and did it and um he was operated on recently. Um And with regards to the, it's quite difficult because there's a lot of um heterogeneity as well, you kind of think, oh, well, you should just be able to do, you know your, your sequences for your, um rectal cancer. But there's variations in sort of um expertise, particularly in, among radiographers who are training, for example, not used to seeing it. Sometimes you get Mris that, you know, are done, they've done a beautiful MRI of the rectum and it's actually a distal sigmoid tumor, for example. That's unfortunate, but it's quite difficult to sort of oversee that. Um We try and sort of train the radiographers as best possible in our own institution. Um But um I know different places have sort of slight different policies we um tell our referral to try and sort of do what they can as best they can. Um But I know some of the centers will kind of just say, you know, if your imaging, they look at it, uh do a preliminary review and kind of say, well, this is not good enough, get it done and send it back. So it, it, it just depends Arrington. Uh Thanks for that. Um I just wanted to ask how effective or accurate is um preoperative MRI of picking up E MVI. It's, it's relatively good, but again, we're sort of looking at a sort of macroscopic level. So this is kind of the, the V two disease which I actually didn't mention in this talk. Um So it's, it's relatively good, but I think it's, it, it requires some experience because I, I certainly also found in sort of earlier days that anything that was kind of going along a vessel, I would just call the MBI, but actually it's more nuanced than that. Um And it has to really be expanding the vessel. Um So microscopic, of course, we're never going to see. But it's, yeah, it's, it's pretty good. But, well, so any added benefit for, for ultrasound, uh apart from, for LT one and T two, considered for organ preserving s or something, any added benefit to the MRI and diagnosis on top of the end rectal ultrasound, you mean? Yeah. Yeah. So as well. So with the MRI, we can also look for nodes that might look involved, for example, particularly in the setting of Tami, right? Yeah. Yeah. I mean the other way around, if, if the MRI is more conclusive, would you consider ultrasound? Oh, yes, absolutely. So, um that uh yeah, that is quite a useful adjunct and it gives you slightly different information. And um again, it depends on what I think local expertise you have, you sort of increasingly, you know, for example, um you know, if you have a tendency to sort of offer partial prostatectomy, but you can kind of say on MRI that there's no sort of frank invasion of the capsule of the prostate and you've got like five or six millimeters to the urethra where you sort of have your dissection plane. You could argue that the end the rectal ultrasound wouldn't have anything on top of that. Um But obviously there are other scenarios where it can't it's certainly a, a useful tool still in this scenario. Yeah, I, um, introduce our group of half a day are in drinking and he, he in the correct for before. Yeah. And also, yeah. Yeah. Ok. Um, so I think you might need to, um, move the chair on the left over a left there. So you start right. So, why do we, uh, ok, we are only 30 minutes late but we will hopefully move the EGM, uh, to after lunch. Um, I've just lost Rob Glyn Jones. He's, he's getting on a bit. He might have wandered somewhere looking for. He's a bit older than wonderful. Oh, he's coming. Oh, yeah. Third one. Ok. Two. Is that so, um, thanks and open and Tom, um, I spent the last six months, um, doing complex cancer and that was that this is something obviously for the exam, but it's, um, when I was in the exam, I will ask it about, uh, t me obviously and, uh, I show the scan with the rectal cancer, ask you to stage it. Uh, and then we went a little bit in discussion about, ok, what it is, what it, if, if it is outside, what, what if it is involving the side wall, do you know about anything else that can be done? So, I'm hoping that you would find this, uh, useful for your, uh, for your exam as well if you haven't done the exam yet. Uh, but also, for when you, we all, we all see these patients, even, even if we, if you don't work in a, in a unit that does complex, uh, rectal cancer surgery. So I, I'll start on the thing. My first question would be to, to and what, what do we actually mean by, uh, beyond, uh, tm. And how did it like, has it been there since we started doing rectal cancer surgery? Um, what, what do we mean by beyond beyond, I have to understand what we mean by is, is any surge goes beyond that heart? And sorry Tom was presenting earlier. Hopefully, you've got an idea what mesorectum fascial pla looks like. So when we choose to do an operation beyond that, because the disease extends beyond that, I direct because of its associated features we might discuss in more detail, we would regard that as beyond T me and it really came into being described as a term. Remember in 2013, there was a conference that we uh consensus conference you before we come out on that as well. Um Well, we got together to try and describe a group of primary tumors that were a bit more difficult that were discreet from locally recurrent rectal cancer. And um we came up with, with the term primary rectal cancer on the TME PR BM is what the game called? Yeah. Is that, is that correct? And this is what it looks like here. Um You can see in the axial there, something very similar to a uh to show that sort of yellow line. I thought the line is in me red fascia. If you have disease within that, you may not need to give any more treatment and surgery may well be enough. But if your disease beyond that, there's some suggestion that you need to escalate the disease based on uh various trials that we, we discussed, but giving something beforehand might make it easier to do the surgery. That was the rationale and you can see the surgical hopefully there. Um Again, these are like the fas pill in the back and in the front and I don't know what the red lines are meant to be per Yeah. So if we go beyond those and transgress those deliberately, then that would be described as be routine surgery. All right, I'm just trying. Oh, the point is working there. Um And um I think my next question too well, what would it mean always that if there is a beyond TME tumor that they would need to have new adjuvant treatment? Is there uh is that, is that a rule, is that that if you, if someone has got a tumor that either extending beyond uh the, the, the mesal fascia there, do we always give them new other in, in general, you are going to want some down staging there to facilitate what uh uh you know what the surgeon's going to do so in, in general. Yeah, I mean, but there may be, there may be other reasons that you don't if the patient's had radiotherapy with prostate cancer and you may select chemotherapy or there may be other contraindications. But I think in general, yes, you're going to, you're going to go down a some form of TNT there. And here's the reason thinking about the radio radiotherapy that if someone had radiotherapy before, can you still offer them a smaller dose? Is that in terms of toxicity? This is, this is a very personal thing. I mean, there are radiation oncologists that think that radiotherapy, radiotherapy is radiotherapy is like Catholic marriage. It's once and that's it. Ok. But I don't hold to that. I think you can give radiotherapy safely these days, particularly with the uh you know, IMRT and things you might well give 35 40 gray compared to 45 50 gray in the past. Um But yes, I think you can reradiate safely provided, provided the patient isn't someone who you clearly have, have already got a lot of radiation damage. Yeah, thank you. Um I, I go back to the first slide again. So obviously, these are big, big operations, quality of life changed. Um We know that patients, it's not like a TME operation where you expect them to stay in hospital for four or five days. And if they haven't got uh you know, a problem, they, they can potentially be home at that time. These patients stays longer. They have. It's, it's a life changing operation. Why, why do we offer, why, why don't we just say, and we're getting back to you, why don't we just offer them either palliative treatment or why? Why this has changed? Um I'm sure it was multifactorial that it's changed. I think people in the past did do operations for more extensive disease and through fault or fall, they found that that was not the right thing to do because the results were really bad. But remember the results for rectal cancer 40 to 50 years ago were abysmal before we understood the importance of an anatomical dissection. So why, why did we do the surgery? Well, um the data I show that offering surgery with a radical excision, cutting out the roots, radical, cutting all the the visible disease is associated with better outcomes. We've learned that from the TME story, the Bill story. Um And we apply the same principles of removing all the disease, a resection and we know that that's associated with overall and disease free survival. The question is, how do you make I know zero happen that all the discussion. Yeah. Yeah. I mean, the, the there probably is no point in doing an operation where you're going to get an R two resection that that's just pointless I think, yeah, I think this comes to the slide that you, you would see that the, the the main aim for, for, for the BMT surgery is to achieve that R zero resection. Um, because if you go into R one R two, probably your quality of life, your, your, um, your survival with an R two is worse than palliative. So, yeah, that's true. That's true. Which is a different category of operation for the C and I think there were other studies, these are too, for recurring, but there are studies as well for, for cli that with a one R zero is the, it is I do. But what I'd also like you to take a look at is what if you choose not to tolerate. And if you look those are Scandinavian data, I think you're sure. So if you best supportive care or palliative care, people don't live, you know, me survivals nine months. Now, of course, that's heavily biased data. Those are patients who is like not of any sort of intervention. But if you choose not to operate and you see that with their own data, for whatever reason, the media spa is only nine months and again, just going back to the indication really when we do extended, I think that's came also from uh that Tom talk earlier. So we do that for either if you have a locally advanced uh the, the TME plane or for um recurrent uh rectal cancers where usually then you don't have that plane anymore and the recurrence wouldn't follow your, your normal planes for, for primary cancers, but also for some persistent and recurrent squamous cell cancer. Uh, and, and it's, it's about 5% of, of the, uh, of the, uh, so I go back to this, so 5 to 10% of the uh tumors we see are locally advanced or so it's not a small number of, of rectal cancer. And we know that 5 to 10% of patients who had surgery also develop recurrence at some points. Um, so I think we'll, um, again, this is just, um, I, I, once I've seen that I've started using it when I chat with my, with my patients in the clinic. And this is something that they get very well. And I just explain to them, this is what we mean by an R you. This is what we want to achieve from, from the surgery. And this is important because when we talk later about surgical planning, this is our aim is to get that complete, uh, safety margin around the tumor. So the yellow is the tumor and the, uh, white area around it is what we want as a, as a clear margin. Then I say if you then have a little bit of that, this is, then you're very close. This is an eye one and obviously we don't wanna see that scrambled eggs. Ok? Um, contraindication, I think this is also something that has changed, uh, in over the last 10 years, right. Yeah, it's interesting. Look at textbooks. Go back 20 years. It was involved with the muscle was that was a contraindication dilatation of the ureters. That was a contraindication involved in behind the sacrum. That was an absolute contraindication of disease in the pelvic cycle, sciatic involved was an absolute contraindication to surgery. Just regard as, you know, we, these list sort of thing. Nowadays, there are certain things that are unchanged. If a patient is unfit, then clearly you're not going to get them through an operation. Uh If they have metastatic disease, that's become previously an absolute, there is a relative contraindication, lung metastasis tend not to kill people. You might be a little bit more liberal about the your balance of operation, big operation pis against that. But metastatic liver disease, it depends on the extent of what we would choose to do the ps. So we we going to consider all the. So if it is treatable metastatic disease, we would consider that ire or untreatable metastatic disease we're very cautious about. Yeah. And um this is what we mean by the surgical planning. So, um and as we, as Tom was saying earlier, we do this obviously on the entity, we look at the tumor, we look at the extent we plan where we're going to do our resection and and it's always variable. It will be something that you do on the right side, something that different to what you will do on the left side, then we document that and on the day of the operation, it's always another meeting that we, you know, we, we had another meeting in the morning just to go through the images again, um push our minds and, and, and then uh discuss if, if how we're going to do it, uh how we're going to start and how we, what what plans we would follow. And you see, so the idea of the mab data in, in some units, they divide it into anterior lateral and central. Er but we believe this is, this was my trip to South Africa a couple of months ago. So, um and my colleagues in South African will remember that. So the um the uh we tended to take into that dotted line is that we, this is the line we will follow uh surgically. Um So we will have a few cases to discuss and um I think we plan six, we'll see how much time we will have to uh hopefully we'll finish up. Yes, I was just going to some interesting is the egg, the boiled egg, there's a room there, another release, probably one of the best paper who read written by jus and years now to go. And that's about hind and the low tide hind ight is when the disease starts. And after the therapy, low tide is where we will be. But unfortunately, the hind tide are going between high tide and low tide, we flats plasma and Jasen on the beach and you tailor the operation around about where the high type of the maximal disease extent is because you're not sure if the regression of the tumor of the low tide is actually coming back uniformly. There might be little fragments of a tumor lying in that lying in its way. So we will often base our operation on the high tide. A low or something that you like. I, I think it, it's, it's something that the bigger tumors uh you know, we, we find fragmentation is much more common in the bigger tumors. The smaller tumors T three A T two tend to respond by, by, you know, what you see is what you get and say that that's it. It's not about what you see on endoscopy or on radiology. It's more about what you see on the specimen later in where your, his pa coming in and how important they are in telling you because they will dictate your treatment afterwards as well if it's needed. I think this is very important because you see patients in clinic and you know that they had a good, they had a good response and the tumor did shrink, but we'll still plan our surgery on our first imaging and, and that makes them because yes, we don't know if that area that has now, that looks better. Now, is it completely completely from small deposit that then can cause local recurrence or not, but it's an important concept, you know, so we will have cases on the lateral tumor extension and how we plan that. And we will discuss what sort of um operation we do for lateral side wall, we'll have something on the interior, anteriorly extending tumors and something on the posteriorly extending tumor as well. Um Just to keep the um I'm not sure if it will run here or not. So OK, we will uh we will have to switch into the videos on the. So this is the first case um starting with a sagittal uh image and we can see that there's a tumor in the mid rectum measuring approximately three centimeters, approximately four centimeters um from the and the rectal junction. You can see posterior there on there's already evidence of transmural extension or something going on in the mes rectum, which is pointing out there with the cursor, the vascular level of the anterior part of the tumor is below that. So now we're transferring to the axial now that we've orientated ourselves on the sagittal. And we can appreciate that tumor morphology which is near circumferential with um rolled edges that approximately 10 o'clock and three o'clock. And we're looking at our leading edge which is in the right posterior quadrants, not by the cursor there with some transmural extension up to at least the centimeter. And then a chunky tumor deposit that's extending cranially in the mesa rectum at the level of piriformis. And that's actually involving the mes rectal fascia that there at seven o'clock. But actually, it's not in the vessel itself. You can see those little black dots around the GMO deposit. So that's why I call it a de positive, not em, the, but however, if you look to the, at about nine clock, you can see that nodular um tissue which is actually within the vessel which is tracking transgressing of the cr the nine block and tracking up to this uh lymph node, which I should in the draw. And you can see here there is an en large node, there's a, a bit of heterogenous signal that perhaps of the spread. So in my mind, I record it, this involved, we wouldn't bother doing a pet scan, for example, for that. And it's just sitting on the sciatic nerve just to show you all the side wall with regards to its position. So we use the superior ute of artery as a, as a marker for a sidewall dissection and that's the superior luteal artery there. So the actual node is below that level. So that's rather uh you're considering clearance on that right side, which we would be in this case. So overall, we've got m rectal tumor it looks like. So it's gonna have um I ask the biology, extra nodal tumor deposits in the eye, coning CRL on the right and involve the no sitting on the uh right sciatic nerve there. This is the pretreatment imaging, which is what we would base the operation on the post treatment imaging have concluded that it was similar and actually has better. But this particular one that corresponds, there's no distant disease. I just also add the ureter on the right clear of any disease. Yeah. Um Thanks doc. Um Shall, shall we go to surgical? Like how we going to surgical be or do you want us to look at the second, the next MRI the second one as well? I think the second one is more, more, more higher up, but let's let's talk about this case. So, so um when we say natural side wall, so tumors and what, what levels in we then when we, when, when we plan surgery, what what are the different? Um you may have a disease that transgresses in these fas the wall. So you have to excise that uh whatever it involves again, that piece. Um you might start at the lowest level. We're talking about levels about lymphadenectomy. That's become very trendy at the moment. I wonder where the pendulum also. Um And that's just cleaning the little fatty tissue in the pelvic sign. Ho we can go into the detail of that maybe later, but that's the sort of lowest level. Then there's extensive disease that goes into the blood vessels, the case that you've seen there, there's the extra capsular sp spread, spread a bit worried that if there's a disease in the spinal. You might want to clear that side wall by taking the blood vessels and take away the nerve that's involved. That's the, the nerve. And you have a more extended disease where it ate everything through all their ligaments fill. See your twos and c your spinous ligaments and it starts to approach one there and then you change to a more radical, more extensive operation and the approach changes often describe the area can be done on this side. We have to do a more orthopedic approach to the girls to get on the side. So yeah, so it's, it's, it's looking at it as the onion skin uh um uh that we've seen in, in, in previous new um webinars. It's yeah, you, you follow, you look at the tumor and you see what, which plane, whether it's uh just lymph nodes in the lymph nodes seems to be encapsulated. You can then say, well, I'm I'm happy that it's just the disease in the lymph node on the outside. But when, when you have this irregular lymph nodes or the from your extension that you know that the vessels, you can't just preserve the blood vessel there or if it is on the nerve, then this is the way you go. Uh I think we can run the second video as well. Uh I can, I just ask a question just as, as a, as a um Does it matter if I've given radiotherapy before. I mean, the, the, the trend for us radiotherapy is that we, we, we're treating that area with higher and higher doses and I it strikes me that we're going to make it more and more difficult for you, the higher doses we, we, we give. So is, is there a, is there a balance between me giving the sort of standard dose, getting some shrinkage and then you going in or is it there a balance where you say? Well, I really don't want to go and do that and you give everything and, and hammer it with SBRT or whatever you like. Yes, I think routine discussion, I we've discussed it based on the individual location and the tumor. But I think as a general rule, if you do just enough to get some spots uh for us to have surgery is more the second view. Um This is the sort of the companion case um looking a sole but uh distal sigmoid um tumor very bulky. As you can see there circum bra are arising in the diverticular segment, both the transmural extension, both anterior and posterior um involving the um the rectal fascia of the sacral promet tree. It's also involving the left ovary cord there and the left ureter. But you can see quite impressively with this case that there's um quite large volume transgression of the endopelvic fascia on the left uh through the ureteral hypogastric fascia, encasing the left external iliac artery and the vein which is being compressed there, know it's the vein because that's how it responds to being squashed. Um And then here we can see where the cursor is. This is the internal iliac artery above the level of the SGA which is contacted by tumor as well. And as yeah, as I mentioned, is involved, so, quite extensive cy or disease which just slightly higher up in the pelvis. Thanks doc. So this is when we can go into not just the big side world, but you would have to go and take other higher up and in independent. Um If we go back to the slides, please uh to the slides again for the presentation. So we talked about in decision when we take a lymph node or a side wall, it could be just a a lymph node involvement. And then you can say we can just do a lymphadenectomy. But if you have more invasion, um this is when you have to take other other structures. And um as you had mentioned, lymph side uh side or lymphadenectomy. Um uh you do that when the nodes are well encapsulated, uh no extracapsular spread. Uh And there is no large volume uh transmural extension or lymphovascular invasion. And you can also do the lymphadenectomy, either above or below the level of the SGA and the superior artery is a vessel that we use a lot. And when we decide what we're going to do because it's a landmark. It's, it's always fixed and it's one of the first things you have learned is how to find the SGA and how to identify it. And then we decide if we, if we exciting the vessels, whether we will excise the vessels above or below the um superior of artery, um you can take vessels, as we said, you can take um uh nerves, uh uh muscles, uh depending on the preoperative surgical planning. And, and this is the, this is where it comes. And one thing that I've also learned is you, you really need a radiologist who, who guide you through this, who, uh uh and, and I think this is, this is the most important fact of surgery as a surgeon is important. But if you were given uh the wrong map, you will just follow it and you end up with an involved margin. Um And this is just, uh uh I think Tom uh really highlighted this about where the SGA comes on the scan. And we mentioned about LC, extended lateral side or excision. I think you, you started this about two years ago as well now. Um and this is where you go deep down and, and uh you take more than just the, the nerves and the vessels that we talked about. Um, so you, you can either take the uh the, the cal spine. Um Again, it all depends on how you can achieve that. Out of the uh section margin. Um So we're gonna now go into the tumor that's extending now anteriorly, I guess it comes more in, in male patients where you have tumor that might be uh threatening the uh the fascia on the prostate tumor that might be then going into the prostate. And when uh when would, how would we decide uh what we can take and what we can leave? Yeah. So this is the, the next case. Um So here you can see on the sagittal and there's that semi well semicircular tumor just at the lower rectum with the coral margin at the level of the anal rectal junction, which I'm now going to look at a little bit more detail on the axial. As I was kind of alluding to the talk, I gave the, you know, looking again to see the roll edges. So we can see them quite nicely there, approximately two o'clock and five o'clock. We've got a leading edge from approximately 8 to 12 o'clock. Um And we can see that we can't see the um muscularis propria. Um We got transmural extension which is involving the right le to there and also involving the um the no fascia for about 10 to 12 o'clock. Um at the level of the mid gland of the prostate also had some um mesorectum nodes which were within the CRM, but otherwise, no em MVI or significant findings good. And we've got some post treatment, imaging as well, which is just coming up. Yeah. So now, so this patient had neoadjuvant therapy, as you can see, actually, has had a really good response to the treatment. So that tumor has become um fibrotic now and shrunk and I can't see any obvious tumor signal. And just anteriorly, we've got the um fibrotic low signal, thickening of the de Noval ase fascia at 12 o'clock. And of course, we can't tell what is fibrosis, what it's tumor. We still got contacted about about 11 o'clock here as well. The nodes that were present um responded really well. So were well within the mesorectum envelope, but I can't see any frank invasion into the prostatic parenchyma. So it's all at the capsule level. So um question to be in here. So with the tumor like this and um the um it, it can be, it's a difficult discussion with the patients and they will ask you what surgery and how, how do you, how do you discuss it with them more? Um Well, I, I think you still see, we see um operation and give you the best chance of getting clear margin clearly. If the disease is into the prostate, then it becomes very difficult to just find doing an operation that it doesn't remove the prostate. And as you know, all the organs like JA and obviously prostate out and the full bladder falls down. So you have to take your bladder as well. So for the most part, there, an extension is actually leading prostate anterior structures. Then the, the, the recommendation is a to these in suggest, but there are some patients where it just brushes up against the brush up against the prostate. And that becomes a discussion of the attitude to risk. Are they willing to take the risk of a positive margin to try and preserve structures like the bladder? Um We do a partial prostatectomy, we do seven ob of excision. Um Those are less than perfect. There's about an 85% risk of a, a complete resection as opposed to a 95% chance of a complete excision with a total. But it's a much lesser operation, the mor less so we can them in certain circumstances. Generally, it's not most people but those with the disease but about in the prostate. Well, they might consider it harm. It's interesting. Most still choose to have a, a total exaggeration. Most people want our insurance type approach rather than necessarily the gamble. There are risk at attacks. You can damage the urethra. You can get a urinary tract fistulas as a result of that. It does mean that they will need a prolonged period of catheterization. But the good news is provided, they get a complete section. Even if they get urinary urethral morbidity, it heals in the majority of patients. And actually, although they might lose the potency, their bladder function is mostly maintained and certainly seems to be no worse than if they had just had an abdominal perineal excision and the functional results of that are not great either. Yeah. Sounds good. Yeah. Um, I think we have another case where there is, uh, more important. So, again, going back radiotherapy with the be offered, uh, if it is, then makes it more, you know, the tumor rego and we see more, more would that support our decision about? Well, we're going to go back and treat on the first initial imaging. Again, that's the discussion. I think almost all of these patients with margin threatening disease, we have a strategy of neoadjuvant therapy. How many of bolt ones and whichever recipe is followed, really depends on the current evidence in the literature on the day and in the MDT. Um but the majority will have had neoadjuvant therapy. I think it would be very difficult to justify proceeding directly to surgery for a certain margin anteriorly in a man and a woman, you might not removing posterior vagina. Again, that's a discussion you would have with them is a little easier to justify doing a posterior vaginectomy without proceeding directly to neoadjuvant therapy. But the majority of mds would not concur that that would be the right way to do it even still. So the other way in the argument, the strategy, if there's a regression, there's a discussion with the patient, we still go based on the original imaging and we would in the majority of patients counsel them. The, the, the optimal choice is a total exaggeration. Yeah. Sorry. Yes. And the, the nice pictures you showed before are nice blank. So, trg one. Yeah, I'd probably call that too because I can still see where the tumor was. Ok. So there'll be some M DTs to say tir G one, tig two. There's a, we, that's what I, how long you wait for. Well, this is it. I, I find this very difficult and, and certainly for sort of t four tumors doing watch and wait. I'm, I'm not a great fan of doing watch and wait and T four tumors to be honest, because I think the patient's got much more to lose. Yeah, great. So I think, well, without running the video, uh you can see the tumor. There is mostly, yeah, that's an easy decision. That's an easy decision. This is where, where we say it's going to be a total pelvic exenteration. Who was the tumor? Mhm. Yeah. I mean, it's, I'd say 1 to 2 centimeters. OK. I mean, it's from the anorectal. So you could leave the, you might, you might lose some bladder, but you might still restore continuity of the Yeah. Um So yeah, total biking sensation doesn't always mean that you will have a permanent colostomy. You can have uh bowel continuity. Um I think the uh the last thing would be the uh posterior component or poster compartment. So, this is something I think that has also changed and evolved and um I'm sure what we offer now wasn't what was offered um 10 years ago. Yeah. So this case, um as you can see, it actually is a distal sigmoid tumor, but you can see um this large tumor deposit which actually um again, on the theme of sort of sometimes not quite getting the imaging right, was not completely captured on the um initial MRI and actually subsequent Mris as well. Um which made our sort of operative planning a little bit harder. So, rather than um doing it completely based on the initial imaging, we had to sort of um go on post treatment imaging once we sort of fully um fully imaged it. So that's just to show the post treatment. So it's become more fibrotic shrunk down in volume, but it's still involving that um fascia just overlying the sacral Pi Montri there. And sometimes we would consider doing a subperiosteal resection, but this is really just too close um to consider that um without compromising the margin, that's just a um line I've drawn when we were sort of helping to plan this surgery, that's where the sort of surgical dissection on that um high subcortical sac toy would be. And then this, we use this plane um to the sort of coronal plane to just have a look to see the position relative to the midline. So, um fortunately, in this case, um it's nice and central disease. Um So we can use sort of the, the, the sacral nerve foramina as the um lateral borders of the, the his um and planning sometimes it's acentric and it's a little bit more tricky. I think we can go to the next video as well just time. And then this case is a little bit more involved. So this patient had a previous anterior resection that you can see denoted by the um the arrow there and had unfortunately had some um anastomotic recurrence which is tracking posteriorly involving the presacral fascia. See thickening of the fascia up to about sort of S 23 level um which isn't too bad. But when we start SRO to the sides, this is now a left sort of para mid line. We can see that this is actually a post treatment scan, but they've had some um tubal perforation in the cavity that's formed. Um And we can see there that it's just if I pause it briefly where the cursor is, it's it's touching bone. So we need to look on other um other planes to just assess where that's touching. We can see vessels which are involved as well. And if we scroll a little bit more, we can see that actually multiple nerves are involved. So we've got L5 S one S two that are all in contact with that. And actually, you can see S3 there, which is um actually looks different from the other nerves because you've got perineural invasion. So, intermediate signal and slightly expanded and that's going into the level of the foramen. Um So that's a sort of an added complexity. It's not just nerve involvement laterally. Once it starts getting in towards the canal, then we have to sort of think about higher resections. This is the axial corresponding to that. There's the piriformis where the cursor was um that tumor up against the, that's just showing the perineural invasion again, compared to the contralateral side. Um And we can see that the tumor is intimately related to the um internal iliac artery. So at the level of SGA coming off um and extending laterally to involve um the bone which will just show on a final um image. So here, we can see that the um where my precursor is that, that tumor is right up against the left sacroiliac joint here. And we can again, appreciate that there's multi nerve involvement. So it's going to require a sciatic nerve resection and a high sa toy along with that TPE. So, and the sign wall as well. Yeah, that just shows that in a different plane you can see sometimes it's much more obvious. So obviously, you can have a, you know, we, we, we separated them into different planes until we left her post surgery, but it's quite often that you have a combination and you would have to do, uh you'll have to involve each compartment. Um I, I think this is when we talk about, this is quite major. This is uh, yeah, and, and the question I ask is, what's the, um, it's a huge ovary. It's very new to the, um, and they would have to know it was worth a while because the morbidity is huge. 50% major morbidity associated with what we got high and win. Um, you also have to balance that. I mean, the quality of life drops precipitous most of the surgery, but by, by year it's kind of climbed up to similar levels by the different ways that we measure your quality of life, none of which are perfect. Um, but if you do it won break, the median was 91. So you can live a reasonable life for about six months and it just falls off per and a reasonable number of dead by you or you can do something that's high and white sort of operation through it. Main, you know, fall off of a 34 years of the six year olds, five years of my or spa is 65%. So even though it's horrible mutilating and it takes a year to recover if you don't die from the surgery, most of them are around for a year or two and about two thirds are five or five years. So there is some value. Now, we need a bit more, we need more. Perhaps we need longer for, just to see what it's like in terms of the quality of life because some of them maybe die after five years, not from cancer but from morbidities and, or also sort of surgical outcomes and that's all you need something more. Yeah. Unfortunately, Caroline, uh, you couldn't join us today but she's a nurse consultant and, and the postoperative, um, follow up and care and the relationship you have with the nurse specialist is, is very important for them. And these patients, yes, they stay in hospital for long. Um But when they come back uh six months or a year down the line of the clinic, um they actually, they go, they need the, the nursing staff at the board because they have spent a very uh sensitive and critical part of their life with them. Um And yes, the, the alternative is um within six months or a year, they would have not survived, but obviously not all of them as well and they would be pretty. So this is just um again, there are previous videos on, on the uh on ac P website about this, the, the planes and um the poster fascia, it, it's just going one layer of the eye to, to, to preserve the, you know, and this is when you then take what we call high subcortical cries. So he where you, we just as size the anterior part of the cortex or the subcortical. Um And it's easier to be done at the. Um So I think I stopped it uh at the top of the Sacrum. Uh when you go down, then this is where you're going to be doing a, a secret. Do obviously a no secret is not as morbid as a high sac. And this is what we always discuss very operatively and uh when I go and sit down with uh Toom and Luke again in middle of this and do it in the uh because this is what we need to follow Interop. And this is when you say, OK, we're going to do a high secret toy at this level or sometime you combine the two approaches. So you do a separate osteo at the top and then you, you, you divide the sacrum at lower down. So, um you don't see any, any surgery, there's different things, there's different uh uh layers that and, and organs that you take and, and, and organs that you preserve. And I hope that we um uh we will cover, um we've covered this in a way that can open it up for you, those of you who would think about doing something like this. Um It, it's difficult to question, it's, you learn a lot about anatomy. Um And uh finally, if you have any uh any questions and then we'll have any final comments from the final, this just talk about how to use the correct terminology. What is the, the term lipid concentration of the section. And again, what's the difference between down staging treatment and correct? Um That is the whole problem with all of this, but you two potatoes and all that sort of stuff. Uh One man's to saturations and the other man's. Well, I know. Right. That's getting confusing as well. Yeah. So the what I would say is we're trying to understand that because we're trying, trying to bring all the literature together to understand what is being done. What the outcomes are is impossible. And for us, our minds have been focused because when we go to the NHS England and say this is expensive. Can we look at better ways of getting this tariff? Is he able to tell us what you're doing? And I think it's, we don't know because nobody's describe, you know, it's all, everybody's got it on term. So we're on, we're on top of that. We've decided we've developed a thing called our pelvic legs, pelvic exenteration and my and all, there's a group of us a pen, we've got it together. I've got a coding system for the extent of the surgery that we do. And it's all based on the sort of stuff that to tells us about the different parts of the operation that are done. So we're doing that and hopefully that'll give us a measure of what actually is happening. And then once we've put all the bone together, we can decide exactly what total exenteration is what posterior exacerbation is, all that sort of stuff or, but then we, we want you to use those terms in the future. It'll be A, an L3, 2, C two, whatever, you know, N one, something like that, that we have our own pelvic exenteration. So a TNM type thing that gives us an idea of what we'll do because I'm sure it'll also show differences in outcome or ability wise, land state and also ultimately on quality out as well. So, yes, just bear with us and we'll give you a better answer in that you can. It's a paper that you can, it is actually a paper that you can actually find the lexicon and see all the different terms. So if you want to be fini neoadjuvant is just an alternative to giving the treatment after surgery. Um So you're just saying, OK, we're going to do it up front down staging is where for reasons whether you want to perform non operative management or you, you need to get some down staging in order to facilitate an normal resection. Thank you very much. Thank the interest of time. We can have more discussion, but I would like to thank the speakers and I hope you find this useful and um we, we'll have another next session from, from ethic room. I'd like to invite her as well. And again, thank you very much. You tell. Yes, I definitely do.