Episode 4 UL CRS

Hello, behind the knife listeners. Thanks again for tuning in. This is Hillary Simon from the university of Louisville, and I'm joined by my team members, Drs. Galandiak, Bulszynski and Kavloukis. Everyone say hi. Hi everybody. Okay. Today we'll be discussing article, an article from the diseases of the colon and rectum and surgical endoscopy, both focused on the management of splenic flexure cancer.

So, let's dive in to our first article. The first article that we'll be reviewing today is titled, Segmental Colonic Resection as a Safe and Effective Treatment Option for Colon Cancer of the Splenic Flexure, a Nationwide Retrospective Study of the Italian Society of Surgical Oncology Colorectal Cancer Network Collaborative Group.

This was authored by Deguglia et al., and it was published in 2020 in the Diseases of the Colon and Rectum. Like many of the articles most recently published on a splen on splenic flexure

colon cancer, this article begins by noting that splenic flexure cancer accounts for about 5 percent of all colon cancers and due to its low incidence and more common presentation at an advanced stage or as an obstruction, leading to higher postoperative complications and lower survival.

Consensus on optimal procedure to perform and the approach has not been determined. The goal of this article was to investigate whether the potentially easier and bowel sparing limited resection could achieve early and late outcomes comparable to those observed after extended resection for splenic fluxure cancers.

This article reviewed a total of just over 1, 300 patients operated on for splenic fluxure colon cancer between 2006 and 2016. Patient data was retrospectively reviewed from the National Colorectal Cancer Network of the Italian Society of Surgical Oncology made up of 31 colorectal surgery referral centers in Italy.

The splenic flexure

was defined as the portion of bowel located from the distal third of the transverse colon to the proximal third of the left colon. The two cohorts compared in the paper were patients who underwent a segmental versus an extended procedure. It is important to note that limbid resection was defined as the resection of the bowel between the left branch of the middle colic artery and the left colic artery at its origin from the IMA.

An extended right colectomy was defined as resection of the last 10 centimeters of the terminal ilium to the middle descending colon, which would require ligation of the iliocolic vessels. The right colic vessels when present in the middle colic artery and in the left colic artery at its origin of the IMA and extended left colectomy was defined as the resection from the middle transverse colon to the rectosigmoid junction, which included ligating the left branch of the middle colic artery in the entire IMA

patients who underwent total abdominal colectomy for any reason, those younger than 18 years of age.

or diagnosis of IBD, diverticular disease, benign or metastatic tumors were excluded from the study. Both arms were balanced in regards to patient and oncologic characteristics. The authors aim to evaluate postoperative complications as well as oncologic and survival outcomes, including number of lymph nodes removed, length of free, proximal and distal margins, and the rate of R0 resection.

The majority of patients underwent limited resection, while approximately 39 percent underwent an extended resection. Of the extended resection group, only about 8 percent had an extended right, while the remainder underwent a left, extended left colectomy. Patients who underwent a limited resection were more likely to have had undergone it minimally invasively.

Overall, they found that limited resections, not surprisingly, had shorter operative times compared to extended procedures, but otherwise post operative

complications and oncologic outcomes were similar between both groups. Specifically regarding oncologic outcomes, Extended resections resulted in longer resection margins.

However, more concerning is the finding that in both arms, the limited and the extended resections, about a quarter of patients had a less than five centimeter distal margin. Meaning these patients received an inadequate oncologic resection of their splenic flexure cancer despite the type of procedure performed.

Extended resections also resulted in greater lymph node count. However, limited and extended resections had similar outcomes in regards to meeting the 12 or greater lymph nodes count needed in an oncologic resection. In the discussion, the authors note that prior works have also noted post operative complications and mortality after splenic flexure cancer surgery to be higher, However, in the present study, both morbidity and 30 day

mortality were particularly low across both arms with no significant difference between the two groups.

The authors felt that their study was limited by the retrospective design as well as potential selection bias and a relatively long recurral period. The lack of details of how the procedure was determined by each surgeon was also a limitation. Additionally, there is no quality of life data reviewed in this study.

To then expand to if, you know, sparing bow in each resection is important based on quality of life measures to know our perspective. You know, to perform our perspective or clinical trial of splenic flexure cancers in light of its rarity would be difficult to perform in the future to gather, you know, higher quality data as well.

However, despite these limits, there was, this was a large retrospective national multicenter study that showed that flexure cancer can be performed and it was done

so the majority of the time using minimally invasive approach with a shorter operative time and a slightly but not significant shorter length of stay.

The authors concluded that because of these findings and comparable oncologic resection outcomes, segmental colonic resection is safe and an effective treatment option for colon cancer of the splenic flexure. Okay, I'm next going to discuss a similar study that came on behalf of the splenic flexure carcinoma study group in Europe.

This article is headed by Nicola DeAngelis, and they basically compared, it's also a retrospective study from multi center it's a multi center study out of Europe where they compared extended right colectomy, left colectomy, and segmental left colectomy for splenic flexure carcinomas. They did do propensity score matching.

Even though, you know, a lot of times we're limited with retrospective studies, I feel like this was actually a very nicely done study. They had 399

patients, so almost 400 patients with splenic flexure tumors. And these the three groups were very evenly distributed 35 percent of them under one extended right, 30, almost 33 percent under one left.

I mean, colectomy in 31 percent underwent the segmental splenic flexure the segmental colectomy. A vast majority of them to three fourths of them or laparoscopic and their primary outcomes were overall survival and disease free survival. They looked at a few post operative measures as far as Ilias blood loss you know, post operative comorbidities.

And then they did dive into path reports to make sure that the notable harvest and everything was similar. And their main conclusions were that there was no differences in observed or disease free survival between all 3 of these groups. So if we kind of break it down a little bit in the details this, as we stated, is a retrospective study.

They define the splenic flexure cancer within 10 centimeters of the splenic flexure

edge. That's going both backwards on the transverse side and going forward on the descending colon side. The, the. Actual definitions for the 3 different operations are exactly similar to the definitions that Dr.

Simon talked about her study accepted. As we know, her study did not include the extended, right? The thing that I thought was interesting while reading it is well, first of all, a few things. I think whenever you read off notes, there's very few people who actually will measure 10 centimeters from the splenic flexure edge.

So that's just a bias of a retrospective study as well as, you know, I think unless you're doing an extended right a lot of times it's quite difficult to actually nail down which order you're taking. You can kind of guess as you're, you know, when you're taking main vascular pedicles, that's one thing, but when you do a segmental you're not, you know, it's difficult to tell what level of the left colic artery you're ligating if you're getting it right off of the IMA, if you're getting it a

little bit closer to the marginal.

So I think a lot of the inherent bias of these retrospective studies is you don't have a consistent ligation point, which may impact your nodal clearance. The other interesting thing is as we, you know, everybody the primary thing we're worried about is nodal harvest. And there is no statistically significant difference in the amount of lymph nodes that were harvested between the three each of the three operations.

However the numbers of lymph nodes harvested did tend to go down with the more limited resections. So the extended right had you know, 97 sorry, 88 percent of the extended rights had more than 12 lymph nodes. 85 percent of the left colectomies had over 12 lymph nodes and 81 percent of the segmental colectomies had over 12 lymph nodes.

The standard deviation of the, of these numbers of lymph nodes harvested kind of, you know, the number of lymph nodes harvested from the segmental colectomies was

18, but the standard deviation was 18. So that also possibly means that you're not getting 12, but it's the same across all the groups.

The standard that the median number of notes harvested in the left was 19 standard deviation of 11. that also actually puts you down below your 12 that you need. And the other thing that they didn't mention is that. You know, the people that don't have 12 with those harvested. Did those patients get chemotherapy because of an inadequate lymph node harvest and they would have been risk categorized into possibly a more risky treatment?

So it's hard, they don't go into the detail as far as how the patients that didn't get 12 lymph nodes, how were they treated? Because that is essentially may have impacted overall, not wouldn't have impacted overall survival, but it certainly is a marker of If we're going to be doing a surgical resection, we want to make sure that, you know, the patient is not going to get overtreated because we did not adequately

get a fair number of lymph nodes.

I don't think that's what happened here, but it's just something to think about whenever you're looking at statistics of lymph nodes that were, if you're going to say that they're, they're statistically the same, they are, but there's some caveats that you need to think about there. They did do a great job with propensity score matching.

So I think that You know, the bigger tumors, people might say, you know, I'm not going to do a segmental on this. We're just going to do an extended, right? And get it over with. They adjusted for all of that. I'm just in for tumor size presence of metastatic disease. Patients in the extended right group did tend to be somewhat sicker.

I think the call again has a slightly lower leak rate. And so I think they felt a little bit safer doing. Ileocolic anastomosis from an extended right with patients who have multiple comorbidities. Other than that, I think that, you know, they also had an interesting finding that the extended right hemi collect me also had a higher morbidity in terms of longer time to resume diet.

Slightly

longer hospital stay. I don't necessarily think that that's significant in terms of their primary outcomes, which was really is this an adequate ontologic operation. So there. I think with their sound solid analysis, their ultimate conclusion was that there was no difference. So with both of our papers coming to the conclusion that most of this, you know, there's no significant difference between a surgical approach.

I guess the next question is, what do we all do in our practice or what does the world do, and there has been a recent, you know, consensus that has been published. Dr. Wolfensee, can you tell us a little bit about that and then we can kind of all comment about our. Our personal thoughts. Yes. Thanks. So the other study that sort of I've read was from the DCR journal.

So it's called the standardization of the definition and surgical management of surgery. Splenic flexure carcinoma by an

international expert consensus using the Delphi technique. The senior author is Dr. Mehmet Kuzu from Ankara in Turkey. And it was published in 2023. So the authors, I guess, identified that there is currently no Definitive evidence based classification to differentiate between splenic flexure and transverse colon cancers in cancer registries or in the potential accrual of patients in clinical studies and of course, to your point earlier, It is a fairly rare cancer, so that makes things even more difficult.

Then the authors aimed to establish the definition the diagnostic modality for tumor localization leading to registration into a cancer database, and as well as this, to assess the surgical technique for the management of splenic flexure cancers. In relation to their methodology, they had a three round Delphi.

The first round, they identified 18 experts from 12 countries all having a minimum of 10 years of clinical

practice. And then the latter rounds they actually got each expert to potentially invite two more clinicians in the same field. And so, The total number of people invited was 47 and 42 were the total respondents.

So first I looked at the definition of splenic flexure carcinoma and they commented on this being 10 centimeters either side of the actual flexure. Interestingly there was a relatively low, Voting rate for this of only 55%. So even, even after three rounds and therefore I think perhaps a consensus consensus statement from either the college or a colorectal society such as ask guys may really help standardize this.

In relation to pre op staging vascular anatomy was not specifically evaluated prior to surgery. And I personally think it becomes fairly pertinent specifically for patients who've had

previous surgery, previous colonic surgery. There was also no comments about continence and the potential impact that may pose on a preference of segmental resection over an extended resection.

Now, in terms of the results in the elective setting, the preferences were such that segmental colectomy was preferred in 78 percent and a subtotal colectomy was preferred in about 60%. Interestingly the definition of subtotal colectomy is As I said, it's a variable It can be defined by the vascular supply.

I think the easiest definition, at least for me, is to state that the splenic flexor was taken down and resected. But of course there is a little bit of a variability probably both regional and within different societies. Now in the emergency setting, 68 percent preferred a subtotal or extended right colectomy and an ileo descending anastomosis.

I guess further to the point about the

sort of definition of the subtotal colectomy. Another thing I would want to raise, or at least I consider in the emergency setting is the necessity for an on table washout. For a colo colonic anastomosis, there was no comment about that. Now that goes for further to then they talked about the lymph node dissections.

So both left colic and left branch of the middle colic were recommended to be divided to achieve radical lymphadenectomy with a 60 percent of respondents stating that 40 percent of experts recommended to ligate. the root of the middle colic artery. And 56 percent recommended a central ligation of the IMV.

I think from a personal perspective I think there were never any comments about the orientation and the origin of lymph nodes either in the histological report or clinically. And I think that we probably could take a lesson out of the. upper GI gastrectomy

cases where they are a lot more dogmatic and identifying when the lymph nodes come from.

And so clearly we have a consensus in relation to taking out more than 12 nodes for appropriate staging. Though to Dr. Cavalucas's point, when she mentioned that segmental resections were noted to have less than 12 lymph nodes, I suspect in extended resections, the amount of lymph nodes around the splenic flexure is probably the same.

And so the histological report claiming that the lymph node harvest is large is likely related to distal lymph nodes. And although there are there is some data saying that the splenic clotes can drain even up to the ileocolic pedicle. I would argue that a bit of that is fool's gold. So back to this study.

Another thing that I thought would be interesting but wasn't commented upon was the anastomotic configuration. So, not necessarily from an anastomotic leak perspective, that would be true. Not feasible to

prove, but from a endoscopic surveillance perspective, clearly an end to end or an end to side configuration would be far easier to scope than a side to side.

And that may be something that's worth considering. So that, that's that's probably my summary for this paper. In regards to kind of bumping it up a notch to our own experts within you know, the society and ASCRS guidelines I know I've read them, there's a brief little, maybe two paragraph snippet, but In the colon cancer ASCR guidelines.

Do you have thoughts or comments on that? Dr. Olshansky. Thanks. Yeah, so I agree. It's, I mean, I take my hat off to the people that devise the guidelines because it's an incredibly difficult thing to achieve. And I think generally they vary. Comprehensive there is a bit about dysplenic

flexor cancers and you're right, relatively to the other areas it is it's probably the lost, long lost cousin.

So. They do mention that colon resections for cancer should generally include proximal and distal margins of five to seven centimetres, which is more in keeping with what I understand, although some of the publications that we've discussed today comment about a 10 centimetre margin. They comment about a minimal, lymph node harvest of 12 lymph nodes, which I think is we have consensus there.

And the thing I've commented about earlier in terms of the potential lymph nodes being involved in other tributaries, they reference that Up to 9 percent of cases do have lymph nodes seen in SMA tributaries, including the right middle and even iliac colic. So, there is very good references to that in the in the guidelines the guidelines state that basically with inconsistency in the reporting data, data,

any individual determination of resection extension based on that.

Upon sort of the feeding vessels of this tumor and together with the functional outcomes should be determined. So there's no one size fits all answer for that. So I think. that was the gist of it. The other thing that they mentioned was that routine extended lymphadenectomy is not recommended.

And particularly complete meso, mesenteric excision has yet to demonstrate a survival benefit. So clearly it is better at sterilizing the local field but what does that mean? We don't yet know. So I guess the question is, Does everyone have a preference, or it truly is individualized every time you step into the operating room with someone who's presenting with a splenic flexor cancer?

Dr. Glandiac? I think it's individualized, or at least I individualize it. I mean, if you look at all these papers and you look at the

BMI of the patients, they're all 25. I can't remember when I've operated on a patient with cancer that has a BMI of 25. Okay. So I think what you can do in a very thin patient is very difficult, different from what you can do in somebody who has a BMI of 50 which sadly we see all too often.

And one of the things that Vlad mentioned earlier also affects on continence. I mean, if you do a extended right hemicolectomy on an older person, they're going to be absolutely disabled. With frequent bowel movements, so I don't think that is all. the right approach to do. And I think there is interesting in a, in about a four year period, there were, I mean, we've discussed several studies, but there were a huge number of very large studies.

And I mean, of thousands of patients, we've talked about how rare these are. I'm not sure how all these series were gathered up, but there were

probably about four or five very, very large series of splenic flexure cancers that were published. We're close to each other, all with exactly the same conclusions that a segmental resection will give you as good oncologic outcomes and that more extended resections were associated with greater complications.

So, I think, unless it's easier, technically, to do a bit bigger excision. due to a bulky mesentery or for some other anatomic reasons, I think a segmental resection is probably a better way to go. Yeah. Does anyone have other thoughts or what they think about specifically when approaching this? I had a particular patient where they had a bulky mesentery.

So, I ended up and he was, came in emergently obstructed. So I gave him an end centrally. transverse colostomy and then I recently reversed him and had a hard time getting

the port that portion of colon to reach the rectal sigmoid junction because I had to take the resection that low. So, if, you know, does someone have a go to of how to Obtain reach when we're working kind of in the upper tier of the colon and, you know, reversing folks because I, you know, I was able to, without doing any fancy maneuvers, get attention free and asthmosis, but it was tough.

I think the biggest part is whenever I. Do them laparoscopically. I mobilize the entire sigmoid colon as if I'm doing a sigmoidectomy, because that will help lift it off of the pelvic brim, so that it can almost You know, just like you medialize it so that you can start, you know, kind of figuring out where your IMA is, you also need to medialize the entire descending colon to get it to kind of reach medial towards your transverse colon.

Do, does anyone often

do a Deloyer's maneuver or a retro jejunal or ileal window in those cases? I've never done a retro ural, but retro ial for, I haven't had to, for the, for a segmental, I've had to do it. If I'm gonna do not for segment. Yeah. If I need to get it to reach the rectum, yes. I've done, I usually do an ileal window.

I think it lies better than a, the lawyer. Okay. Dr. Mosinski, do you have any comments? Yes, I think, and I hope that Dr. Gandia would agree with me. I think an end to end anastomosis is just so. And it really saves the amount of bowel that, that might be consumed by a side to side. And so for me I find a lot more reach with an end to end.

The other thing I think is incredibly important is to confirm pulsatile blood flow. at both sides of the conduit, which is different to say an anterior resection where I would always confirm

postal blood flow in the descending colon, but I would never from the rectal side. And I guess there is also variability in the Perfusion of the splenic flexure being the arc of Ray Allen commonly been mentioned is a factor.

So, the other thing I want to mention is the comment about the BMI. Recently, I've been lucky enough to be involved in a publication where we looked at the difference between BMI and central obesity or visceral obesity for For TME and certainly BMI, we all know is not really a good indicator for mesenteric fat.

And there is difference in female and male distribution of fat. And so I think sometimes, although that's probably still the best surrogate we have but you can have someone with a high BMI an incredibly difficult mesentry, which is more common than a male or relatively speaking, a far easier mesentry being in a female wear.

the sort of obesity distribution is to the hips and thighs and away from

the colorectal areas. So, so, to that point I think earlier when Dr. Cavalucas mentioned the propensity scores, I think it's a difficult thing to measure. And this is another limitation in retrospective trials where where there is a significant difference.

Yeah, I think that's about it. I've got a question because this happens, you know, every time something happens to you, once you worry that it's going to happen to you every time you do this case, but what do you guys do with your very large mesenteric defect in an area where there's a lot of upper small bowel?

Like if you're going to, if you're going to anastomose, I did a hand stone end to end. you know, prox you know, mid transverse to descending colon that went fine. And I would say within the first two months post op, the patient kept coming back with early satiety because her, her small bowel had kind of slid through that rather large mesenteric defect be underneath my colon.

And it's not, it's not as simple as, Oh, you

do an ileocolic resection, just, just suture your mesentery together. Cause the mesenteries are really not that close. Yeah, well, I mean, a lot of times they will just stick down, but there's a very big one. I'll try to approximate it to the retro. Okay.

Approximation. Okay. I think closing the mesentery is not, not, not without its complications either, and I've kind of, I've oscillated from going to closing everything to having a mesentery bleed, which, which was very unpleasant both during the case and subsequently to then not leaving anything closed.

The other thing is interesting in patients that don't make adhesions, then the question becomes, well, what do you close it with? Because if you close with a dissolvable stitch, does it really matter? And the other option is, would it be simpler to plug it with Omentum rather than approximating it?

So there's a few different considerations, but I don't think anyone

has a perfect answer. And I know we talked about some anatomic considerations of, you know, the marginal, um, and all of that. But do you think there's any role for 3D CT angiography or interop ICG specifically for splenic flexure?

Cancer sections, or I know there are some papers out there talking about this, that it's obviously feasible, just like we use intra op ICG for other resections. Does anyone here do that routinely? Yeah, I do ICG routinely. I mean, if you're using the robot, I think it's so easy because it's a built in, so to speak.

Sure, sure. But even our lab systems now have ICG capability. We have a capability for open too. I think that that is particularly is one area that Your blood flow is notoriously not great, so I just feel good with the ICD glowing. I mean, a lot

of times if it, if it's not available or if it, I mean, it's very easy just to also check the blood flow.

If you're exteriorizing the colon and you look at it, cut it and see bleeding. I think that's a very convincing thing. But I mean, splenic flexure is, you know, an area where, especially in older patients or people who are smokers or have vascular problems, or if you've had somebody be very rough with the bowel, particularly in the area of the marginal artery and you're worried about it, I think it always is good to check on perfusion.

Yeah. By some means I know, again, this is just a topic that is there's no true consensus like we've already touched upon. But if we had to leave the listeners with, you I know we'll go over our five quick hits, but just to kind of wrap up with anything that we would want them to take home in regards to operating on splenic flucture

cancers.

Is there anything anyone can think about or wanted to, you know, also comment on today? Yeah, I think that the oncological division of the middle colleagues is no less difficult than achieving a. But it sort of lacks the spotlight and particularly I think we're far more comfortable operating in the pelvis than in the sort of upper quadrants of the abdomen which, which adds far more sort of stress or cognitive difficulty.

And when I compare my approach, like for every other bit of the colon, I have an algorithm, which I did not deviate from and I'm a strong believer. in reproducibility and doing the same operation. Yet for the splenic flexure I kind of go against my own philosophy and I tailor it to what I think is in the best interest of the patient, which does open it up to far more complications because every time the case is far more variable.

And I haven't really married the two competing interests. And

so I think it probably lends. This cancer or this area lends to far more preoperative analytical thought and preparation and particularly early on to a revision of the different steps so that you're not making it up during the operation and that you're sort of on a little bit more of an autopilot.

So I think this is the cancer which for me. Is the one that I would spend far more time both discussing with the patient preoperatively and also just, you know, before the case on the day, actually genuinely thinking about it, not that I don't think about others but this is the one which I think is good question based off of that.

So, on Monday, I have a 37 year old male with a very strong family history of Lynch syndrome and his MSI. Testing is in particular is pending, but I'm certain that it's gonna be positive. 'cause literally every person in his family is is MSI high and he has aple flex cancer. So do you do an extended right on that

person?

Because they have Lynch and they have it. Like if the ace, that's a different case, right? But I mean it's, I think this is to Dr. This Isky point is that this is one per, you know, I think that. Dr. Simon's points with our five quick hits. It's that all of the operations are equal. They're all acceptable. And in this case, you know, you may really need to tailor to individual.

Yeah. Yeah. Yeah. Yeah. Some total for that. I think one other important thing is if you have a gastroenterologist who will send you a patient who has a quote descending or proximal or distal transverse colon cancer, it might be worth either if they haven't been tattooed rescoping them again, or getting a CT to just Exactly localizing that cancer so that you can discuss the treatment and formulate a plan for surgery.

And then always bowel prep these patients. I think the more optimized they can be to, to Dr. Bolshinsky's point earlier the better for this tricky area to operate in someone's abdomen. With kind of our time coming to an end here with our splenic flexure journal club review for colorectal surgery We'll go over some five quick hits for you to take away with you today number one, remember limited and extended resections result in similar overall survival.

Surgical procedures should be individualized with a focus on preoperative planning being a priority. Don't forget to assess perfusion of your bowel prior to anastomosis. An asthmatic configuration should be tension free and easy for endoscopic surveillance. And trust and verify location of tumors of the splenic flexure endoscopically.

Thank you all for your

attention, and until next time, dominate the day.