Well, welcome, everyone. Good morning, good evening, good afternoon, everyone. I'm Dr. Lim in Reno, Nevada, in the United States. So we're going to talk today, this morning or today, surgical staging for gynecological cancer, the indication technique and management of complications. I know some of you are in various parts of the world. I'm not sure that some of this technology that you have available, for example, sentinel lymph node technology. But just can you just tell me, does everyone have the ability where you are doing laparoscopic surgery, if you will? Oh, you're muted. Yeah, we don't have it, sorry, in Nepal. We don't do sentinel lymph nodes and we don't do laparoscopic also. It's like laparoscopic is basically for a very basic diagnostic or simple ovarian system. OK, well, I apologize that some, I mean, this is going to primarily focus. I didn't quite understand what different parts of where you are, regions, what technology you have. But I still think that there's a learning that you can do. You can learn from this, hopefully, the lecture, mainly the anatomy and technique and all. And the technique basically applies the same principle. You have to, I always say, I was always taught by my mentor that I taught myself laparoscopic surgery and robotic surgery. And how I taught myself was applying, I was trained as an open surgeon. And all the basic techniques that I learned from the open surgery, I applied to laparoscopic and robot too. OK, so with that, we're going to talk about surgical staging for gynecological cancer. Let's see, my, it's not forwarding. I'm not sure why. Oh, here we go. All right, the objective for this morning is indication for surgical staging for GYN cancer. Primarily, we're going to talk about pelvic and aortic lymph node dissection, review of the anatomy, technique and management of complications associated with this procedure. Dr. Lim, we can't see your slides. Oh, you can't? No. Oh, I apologize. Sorry, I realized that you were trying to forward and we can't see them. OK, wait one second. I, that's, let me see. I have to share it. I forgot to share it. Yeah. Let's see. How do I get, I don't see. Down at the bottom, you see a big green button says share screen by your chat. Yeah. OK, I'm trying to post attendee. I don't see that screen. You don't see the share screen. You see a mute, stop video buttons. Hold on a second. Says Zoom more than meetings. Post attendee, no. No, like if you bring your cursor, like your mouse down to the bottom, sometimes it pops up like the mute. I'm going to bring this, here we go. Mute, OK. I don't want to mute. No, but you should see a green. I see it. I share screen here. OK, I apologize. No problem. Video, share. I was supposed to do that. There we are. There we go. OK, you see that? Yes, we see. There we go. You see my slides now? Yep, there we go. OK. So we're going to talk about. If you want to start from the beginning, that'd be great, just to say a couple of people started. OK. Thanks. So we're going to talk today about surgical staging for gynecological cancer, indication, technique, and management of complications associated. So the objective for this morning's lecture is when the indication for it. And the pelvic and aortic lymph node dissection, primarily review of anatomy, which is very important, the technique and management of complications. So when is an indication for surgical staging in GYN cancer? So in cervix cancer, at least around the world, the standard of care is to do a pelvic lymphadenectomy. And in certain situation, one would do aortic lymph node sampling depending upon if you have locally advanced cancer. In the US, sometimes what we will do is we would do a sampling to assess whether the aortic lymph nodes are involved so that we can better plan radiation field. The role of sentinel lymph node is something that is new in cervix cancer. It's not the standard of care yet. But with the technology being present, that's something that in the future that will evolve. Endometrial cancer, as you all know, previously pelvic and aortic lymph node dissection was the standard of care to assess the endometrial cancer. Majority of the endometrial cancer is early stage. So not everyone requires a pelvic and aortic lymph node dissection, at least in the last five years or seven years, I should say, probably in 2015. The role of sentinel lymph node in staging as part of endometrial treatment for endometrial cancer has evolved and has increased. With ovarian cancer, it is critical that at least for early stage ovarian cancer, one, you want to make sure that you do an adequate pelvic and aortic lymph node dissection primarily up to the level of the renal vessels. So when you're performing the aortic lymph node dissection, it's really, I want to go over with all of you the anatomy. The anatomical landmark is really critical in identifying the space that where you need to perform the lymph node dissection. So as GYN oncologists, we always say retroperitoneum is our friend. And the reason why is because that's where all the important anatomical structures are housed. And the pathology, the anatomical structures are constant. So for example, the pelvic side wall vasculature, almost 99.9%, you're going to rely on that external iliac artery and vein. And the aorta and the vena cava, that is constant, that's not going to vary very much. The ureter, on the other hand, depending upon what kind of surgery, sometimes the ureter can be displaced due to either pathology or due to previous surgeries and all. So I want to make sure that you are aware and you become familiar with the anatomical landmark so that you can appropriately set up the surgery so you can successfully perform the pelvic and aortic lymph node dissection. So as we all know, ureter is a retroperitoneal structure. And one of the constant that you have to remember is the ureter always crosses over the common iliac vessels as it enters the pelvis at the level of the pelvic rim. So a couple of spaces that I want you all to be familiar with when you're doing the pelvic surgery, we as GYN oncologists, this is the space that we live in all the time, the paravesical space and paraerectal space. There are two spaces, symmetrical bilaterally here, you can show. And the boundaries, you have to really know. So the paravesical space boundary laterally is the external iliac vessels. And medially is the superior vesicle artery or the obliterated umbilical artery. Anteriorly, it is bounded by the pubic bone right here, you can see. Posteriorly is the cardinal ligament complex, the parameetral complex. The important structures in the paravesical space, you can see, is the pelvic vessels, the iliacs, the obturator, artery, vein, and nerves. Paraerectal space is more posterior and it is bounded laterally by the external iliac vessels, medially by the ureter, okay? And anteriorly the parametria and posteriorly the sacrum. And the important structure that houses this paraerectal space are pelvic vessels, iliac vessels, the obturator, artery, vein, and the hypogastric nerve flexors and the ureter. So these are the anatomical landmarks that we rely on. So some of you may not be familiar with the robot and I'm not saying that this is wrong. So I do a lot of robotic surgery and robot is the best way to really, really learn the anatomy. When I was a resident or a medical student, you're on an open surgery, you're the third person nearby the feet of the patient and you can't really see those spaces and your attending basically says, well, this is the space and you can hardly tell. So the robot really tells you these spaces very well. So this is the right pelvic sidewall. This is the ovarian vessels that we're gonna, and so the anatomical landmark is the ovarian vessels. This is the right ovarian vessels and we're gonna retract it medially and open up the medially for the peritoneum, the broad ligament, the posterior part ligament. You can see the right external iliac artery and vein and the ureter right here, okay? That's where I identified the ureter and as soon as I identified the ureter, we retract the ureter medially and the lateral boundary is the external iliac vessels. And here it is, here is your pararectal space and here are your hypogastric nerve plexus. This is an avascular space that you develop. This is the obliterated umbilical artery and if it's an open procedure, what you would do is you would identify this, retract this medially, open up your anterior broad ligament and basically open the paravesical space. And I'm gonna hold that right there. So you can see that paravesical space is here, pararectal space is here, external iliac artery and external iliac vein. The ureter serves as a medial boundary for the pararectal space. I have the ovarian vessels retracted medially. So here is the obliterated umbilical artery. So the paravesical space bounded medially by the umbilical artery, laterally by the external iliac vein and artery, okay? The parametria posteriorly and the sacrum anteriorly. Here is the Foley catheter. The pararectal space medially is bounded by the medially for the peritoneum and the ureter. That's the first anatomical landmark that I see. Soon as I identify the ureter, I come drop right down to develop this pararectal space. The external iliac artery and vein is here, and this is the sacrum, okay? So this is the space that's developed. You can see that this is the ureter. And then when we start the lymph node dissection, we basically start laterally. Okay? So you want to start on the artery because you don't want, as you know, when you're starting the lymph node dissection, you're going to grasp the lymph node. And if you're doing this on an open procedure, same technique, you're going to grasp the lymph node away from the vessel, and you're going to start laterally to the artery. I always like to start it on the artery because the arterial wall is more forgiving. It's the thicker wall. So you're going to come, dissect, start from the common iliac, and then mobilize the tissue all the way here. Here's the divided round ligament. Okay? We're going to retract that up, and then you're going to retract laparoscopically. You're going to retract the obliterated umbilical so you can open this space up. And then here is your circumflex, and you're going to mobilize right here. If you were doing this on an open surgery, same technique. You're going to bring a deeper into this paravesical space and retract it. The first vessel that we look for anatomical landmark is your accessory operator vein. Okay? This is the pelvic sidewall, and we're going to retract the lymphoid tissues laterally. You can use meds and balm. You can use a cautery tip if you were doing an open procedure, or laparoscopically, same thing. You're going to retract the vessel here. Here's the external iliac vein, and we do a lot of skeletonization. And then after what I call the level one lymph nodes removed, which is the external iliac artery and vein lymph nodes, we're going to drop right down to the obturator fossa. The first landmark identifies the accessory obturator vein, and from there, we work distally to proximally, or anteriorly to posteriorly, and we're going to identify the obturator nerve. So there is the obturator nerve. Here is the pelvic sidewall, and we're going to skeletonize this. Here's the obturator nerve, and we're going to skeletonize the vessels off the pelvic sidewall. This is the ischium bone, and here is the obturator nerve. The obturator artery and the vein is below the nerve, so we're going to have this retracted, and you're going to have retraction here. The ureter is there, right here, as it crosses the common iliac vessels, and we're going to mobilize all the lymphoid tissues off the vessels, and we're pulling, gingerly pulling. So if you have met scissors, you're going to come right between the junction of the vessels and the lymphoid and mobilize it, okay? So that is the paravesical and pararectal space. Now, when we do Perry aortic lymph nodes right here in this region, you're going to have the right aortic lymph node basin and left aortic lymph node basin. The anatomic so how I perform the aortic lymph nodes is I call it the four box technique. As you can see I divide the IMA is the center, and I divide it right down in here to a four quadrant. This is the right infra IMA right supra IMA left infra IMA and left supra IMA, or the infra Reno know. And when I do my periodic lymphadenectomy, that's exactly how I pursue that I start from the common and work my way up. And then after I do the complete the right side. I do the left, and then work my way up the technique of exposing this operative field is the same, regardless of what surgical technique, if you do an open procedure. This is what we call the transparent to new approach, and I'll show that to you in the video later. If I do a laparoscopic periodic, it's the same exposure, the same technique to get the operative field exposure. Okay. What you have to remember is when you're doing this procedure, the anatomical landmark serves as the boundaries, so that you can be in an appropriate operative field to remove the lymph nodes. Okay. And the anatomical landmark box number one, which is right here, is the right infra IMA. Laterally it is bounded by the ureter, medially by the aorta, and superior boundary is this imaginary line where the IMA bisects in half. Okay. And inferiorly boundary is your common iliac vessels. As you move up to box number two, which is the right supra IMA, the right ureter and ovarian vessels are, again, your lateral boundary, aorta is your medial boundary, and the inferior boundary becomes the IMA, and superior boundary is this right ovarian vein and the duodenum. Okay. So we'll show that to you on the video. The left infra IMA, the left ureter is the boundary here. The left common iliac is the posterior or the inferior boundary. The medial boundary is the vena cava. As you march up to box number four, the ureter is your lateral boundary, medially is your vena cava, superior boundary is your renal vein, and the inferior boundary is that imaginary line for the IMA. One of the anatomical things that you should remember is this anatomical relationship of the ovarian vessels to the ureter. The way I remember that is the ovarian vessel or the ureter, u under, so ureter is under the ovarian vessel. So if you pick up the ovarian vessels, it drops down immediately inferior to if you're trying to find the ureter. This is again a robotic approach of a transperitoneum in the anatomical landmark that we're showing. So here is the right ovarian vessels right here. We've opened up the peritoneum right here, and here's your right common iliac. This is the psoas muscle, the right common iliac. So this is the inferior boundary, and here's the right ureter. So as soon as after we incise the peritoneum, we basically push, you want to leave the ureter on the medial leaf of the peritoneum. If your ureter is not lateral, serves as a lateral boundary, you are in the wrong space and you're going to get into a lot of bleeding. So make sure when you're incising this peritoneum, you're going to first look for the ureter on the lateral aspect of it, and you're going to push this peritoneal edge that we've incised. This is the same approach that you would do whether you're open, laparoscopic, or robot. So you can see that I have this peritoneal incision open all the way up and on. So here it is. That's the ureter and the psoas muscles right here, and these are the lymph nodes. And after we've moved up, here is the left common iliac. We identify the left common iliac and we drop right down and identify that ureter, which is attached to the medial leaf of the peritoneum, right there, you can see that. Once we've identified that, we can then retract that ureter away. We can identify the ovarian vein, which is above, here's the IMA. This is box number four, and we follow the course of the ureter into the left, actually the ovarian vein into the left renal vein. See that? Any questions? So this is the left periaortic lymph node basin that I just showed you on the common iliac of that. So box number three here, the ureter is on the lateral boundary. The medial boundary is the vena cava and the common iliac is the inferior boundary and the IMA is the superior. So when we talk about pelvic lymphoanectomy versus sentinel lymph node, which is better? So there was a large series that was done at Mayo Clinic, the lymphoanectomy and Memorial Sloan Kettering Institution. Two institutions in the U.S. that's very well respected in U.S. cancer center. And they evaluated, this is Erickson comparison of sentinel lymph node and selective lymphoanectomy algorithm in patients with endometrioid cancer with limited myometrial invasion. When they evaluated that, they found an incidence with sentinel lymph node 2.6%, aortics is about 1%, myometrial invasion absence about 25%, and the three-year disease-free survival is shown here. So what they have shown is what they conclude, either strategy, whether you perform a lymphoanectomy at Mayo Clinic, which is the incidence what they found, and Memorial Sloan Kettering, which they performed sentinel lymph node, they're equivalent. So conclusion, either strategy for endometrial cancer staging shows no apparent detriment when you perform sentinel lymph node sampling rather than the full pelvic and periodic lymphoanectomy. Now these are, you have to remember, the subset of patients of group is early endometrial cancer with minimal myometrial invasion. Now why is limiting your pelvic periodic lymph node dissection is important? Well, as you know, one of the complications of what performing pelvic and periodic lymphoanectomy, particularly patients with cervix cancer or an extensive lymphoanectomy in an ovarian cancer staging, patients can develop lymphedema. And you can basically see the various stages in all of that. This can often be exacerbated if you require radiation following a lymphoanectomy. So what's the rationale for sentinel lymph node dissection? Well, it's important in staging because it helps us determine prognosis, and it helps us determine whether adjuvant therapy is required, and it may impact overall oncologic outcome. The reason for doing the sentinel lymph node sampling rather than a full lymphoanectomy is to decrease morbidity, but what we want to make sure is we don't want to compromise the detection rate of the lymph nodes involved. So what do we need to know about the sentinel lymph nodes? And some of you may be in regions where you may not have this technology, and I apologize, but I think it's important to know that there are different types of tracers that are available. And how do we detect the sentinel lymph nodes and all? And how much should you inject? And where do we inject? And what's the technique of injection? So I'm going to go over that with you somewhat. So the different types of tracers, I think you can get blue dye in certain region of it, radiolabeled colloid, you're going to need obviously isotope. In the U.S., we use endocyanide green. It doesn't necessarily have to be with the robot. You can use this via the laparoscopic, or you could use the technetium 99. For majority of you, probably this is not available, or the radiolabeled colloid. Probably ICG may not be, but blue dye is a way that you can perform a sentinel lymph node sample. What should be considered when we're considering sentinel lymph nodes? So patients that have endometrial confined to the uterus with no obvious mets, demonstrated by imaging studies or extra uterine disease at the time of the exploration. This is what sentinel lymph node sampling at this point in time is. Now what about the detection of blue dye with technetium 99? So technetium 99, you may not have that technology available for majority, but with the blue dye, 80 to 85% yeast tracers alone, nearly 90% when used together. The problem with blue dye, if you're going to use a blue dye right here, as is demonstrated, it undergoes rapid dispersal and patients could have an allergic reaction. Technetium 99, for majority of you, you may not have this technology, expensive, painful, whereas gamma camera techniques, training and radioactive. So we normally don't use this technique in the U.S. at least. If you look at the literature of sentinel lymph nodes, that basically for cervix and endometrial cancer, these are various authors that have looked at the sentinel lymph node mapping and you can see that the mapping primarily can range anywhere from 67% using ICG dye, nearly to 100% with the various dye usage here. And I think part of the reason why you see the variation of it, part of it is the dye, part of it is technique and all. If you evaluate lymphatic mapping of pelvic lymph nodes and endometrial cancer, where the sentinel lymph node, where it resides, where it can be detected, is distributed. But most commonly, it is the external iliac lymph node followed by the obturator lymph node. And you can see the incidence of this where lymph nodes can be detected on sentinel. So is there a need for preoperative lymphocentigraphy? So 50 patients underwent this triple injection with preoperative lymphocentigran and they did a technetium 99 and blue dye. There was no correlation for number and location of lymph nodes, what we found. There's no metastatic nodes were identified by preoperative lymphocentigraphy alone. So conclusion, there's really no added benefit utilizing preoperative lymphocentigraphy. Here is the center core study looking at 139 patients performing 300 and sentinel lymph nodes in 100 patients and lymphocentigraphy detected about 87% while lymphatic mapping detected nearly 97%. So the only potential important finding that lymphocentigraphy identified is the unusual drainage pattern. So it may help to find nodes in unusual places. What about the evidence of mapping in endometrial cancer? This is primarily just the endometrial cancer looking at and these authors primarily had used ICG and blue dye. Again, the mapping ranges anywhere from 57% bilaterally to nearly 97% detection of the various. So it is a very, very sensitive testing, if you will, the sentinel lymph node. And the overall rate of metastases that is detected via sentinel lymph node mapping, that's been published by these various authors, nearly 1200 patients. The macro metastasis is about seven and a half percent. The micro metastasis is about 4% and the isolated tumor cells is detected about three and a half percent. Total lymph nodes detected is roughly about 15% when we use sentinel lymph node mapping. How accurate is sentinel lymph node in high risk endometrial cancer? So remember what I said initially for early stage. So in low intermediate and high risk patient with endometrial cancer or type two endometrial cancer, such as uterine papillary cirrhosis or carcinoma sarcoma, is sentinel lymph node mapping adequate? Well, this was a study done by various authors. This first one is by Memorial Sloan Kettering, looking at serous uterine carcinoma, nearly 248 patients, sentinel lymph node and 153 in 95 have pelvic lymphadenectomy. The median number of lymph nodes removed for the sentinel lymph nodes were 12, while pelvic lymphadenectomy was 21. The median number of positive nodes were similar. There was no difference in median two year progression survival when you use in the setting of serous carcinoma of the uterus, usually if you perform sentinel lymph node or pelvic lymphadenectomy, they didn't see any difference in it. Is there a role for sentinel lymph node in carcinoma sarcoma of the uterus? Well, this is again, the same group from Memorial Sloan Kettering looking at specifically carcinoma sarcoma of the uterus, they evaluated 136 patients, where 48 underwent sentinel lymph node, while 88 nearly two, two times more underwent pelvic lymphadenectomy. You can see the median, the number of lymph nodes removed in the median number of positive lymph nodes were similar. And again, in the medium progression survival, it did not make a difference. techniques, whether you use sentinel lymph nodes or pelvic lymphadenectomy. This is the MD Anderson study looking at specifically high risk endometrial cancer. These are deep myometrial invasion with grade three endometrial adenocarcinoma. This was a prospective validation of sentinel lymph node mapping for high risk. 123 patients underwent the sentinel lymph nodes and the detection rate was nearly 90%. The bilateral detection rate was 60 while unilateral was 40% and 2% was peri-aortic. They use various dye ICG 61% of the time blue dye was 28 and blue dye and technetium comprise of 11%. The overall sentinel lymph node sensitivity detected was 95% false negative rate was about 5% while false negative predictive value was 1.4 and if size specific lymphadenectomy was performed when sentinel, sentinel lymph node was not detected, the false negative rate was decreased to 4.3%. So basically what this is saying is, is, is that, you know, this paper shows that sentinel lymph node may be sufficient to perform in high risk, but you can only detect nearly about 60% of the time bilateral detection and your false negative rate will be increased if you're going to utilize sentinel lymph node in the setting of high risk endometrial cancer. If you only have the sentinel lymph node detected on one side and not the contralateral side, you have to perform the pelvic lymphadenectomy on the side that you did not, you were not able to map the sentinel lymph node to increase the detection rate. So what is the less geo sentinel lymph node mapping guidelines say? Well, you have to, you know, these are the recommendations, you have the expertise of the surgeon and attention to technical detail are important factors for mapping. And what they basically say is superficial and deep cervical injection of dye is a useful and validated mapping technique, complete evaluation of peritoneal cavities required if you're going to use sentinel lymph node mapping for clinical stage one. And sentinel lymph node detection begins with evaluation of retroperitoneal spaces so you have to open up your guard leaf ligament and the peritoneum overlying the aorta to really explore to determine and evaluate the sentinel lymph nodes. Any suspicious lymph nodes should be removed regardless of sentinel lymph node mapping and frozen section analysis may influence the decision to perform periodic lymphadenectomy in some cases. And that's how I approach it and I'll speak to that shortly. However, a routine frozen section of sentinel lymph node is not recommended because of the relatively low sensitivity for detection of mets and normal apparent lymph nodes. Performance of hemipelvic side specific lymphadenectomy for mapping failure has been shown to reduce false negative staging. That's a key point right here. Continuous pathology evaluation of sentinel lymph node with serosectioning with IHC stain increases the detection of low volume mets. These are the SGO recommendations. So here is the injection. What I like to do, this is showing the mapping. Some surgeons like to inject at the four quadrants. So you can see this is at 12. This is for showing the cervix. I like to inject at three, three o'clock and nine o'clock. I do a two quadrant injection. Typically what you want to do is you want to inject to a depth about two millimeters. But more importantly, it's the feel of it. The feel of it as you inject, you should have some kind of a pressure of resistance. If you're injecting the ICG and if it goes really, really with minimal impedance, there's no resistance and it just flows in, you're in the wrong space. You want to be able to feel that back pressure and some resistance to that. So how we pursue endometrial cancer is we basically start off with retrieving the sentinel lymph nodes and we actually perform frozen section of it. And then while waiting for the frozen section, we perform a hysterectomy, we go on and proceed with the hysterectomy. That way, as the frozen sections we perform, we can complete the hysterectomy. And by the time that the hysterectomy is completed, we would normally get the frozen section results. And depending upon what the hysterectomy specimen says, if there is no mapping, we would perform a size specific lymphadenectomy. If it's no myometrial invasion or invasion less than 50% with grade one, no further surgical staging will be carried out. But if the patient demonstrates that they have deep invasion or grade three or high histological type, a full surgical staging will be performed. And so we're going to move along to the ovarian cancer staging. So with the ovarian cancer staging, this is the detection rate of the minimally invasive surgical approach. And these are various authors that have performed laparoscopic staging for ovarian cancer staging. So you can see U.S., Canada, Italy, Belgium, Italy, and Korea, and the operative time for these various procedure and the number of lymph nodes and of the pelvic lymph nodes that is retrieved and the number of periodic lymph nodes that are retrieved and the length of hospitalization. I know that different parts of the world, hospitalization is different. Some may be much longer and in your region, in the U.S., we really try to get patients home early with these minimal invasive surgery. More importantly, the detection rate or the upstaging when we perform periodic lymph node dissection range anywhere from 5.9% to as high as 26.7%. The advantage of minimally invasive surgical staging, the pelvic periodic lymph node dissection is that you have low morbidity. These are the various complications that have been reported by these various authors. So this is basically a demonstration of laparoscopic pelvic lymph node dissection, similar to the technique that you saw that was the robot approach. We start with the, again, this is the sentinel lymph node detection. This is ICG endocyanide green that we detected. Here it is. You can see the ICG lighting up here. Here it is. The sentinel lymph node. And again, the same technique that we're used. We open up the posterior abdominal ligament. Here's the right ovarian vessel. We've identified the ureter, that's medial boundary, and the external iliac artery vein. And then basically skeletonizing the lymph nodes and retrieval of the sentinel lymph node. And I do a lot of skeletonization when I'm doing the lymph anectomy, even on an open technique. I want to make sure that I'm very well away from the vessel, mobilize the lymph nodes off the vessel. Here's the external iliac vein, and we can see we truncate this and isolate the vessels and basically dissect and retrieve the lymph nodes off the vasculature. And this is, again, a similar procedure using laparoscopic. So this is what you want to do is you want to incise the anterior and posterior broad lymph ligament, which we're doing right now. Open up your paravesical and rectal spaces early on. We've identified the ureter right here. We're going to open up the anterior broad lymph ligament, incise it up to where the obliterated umbilical vessel. That's where we identify. We're going to retrieve that, have my assistant retract this, grasp this peritoneal edge. We're going to open up the paravesical space right here. Here's your external iliac artery and vein, your lateral boundary, and here is your medial boundary. And your assistant basically come under here, and then with the retractor, pull. Now, if you're doing an open procedure, you want a retractor in this space so that this is all retracted to expose the vessel, okay? Same technique we're using. And once we have that, we're going to start our dissection laterally and cephalad. So we're going to come right at the junction between the psoas muscle and the external iliac artery, and we're going to skeletonize, come all the way down, and then identify the distal boundary, which is the circumflex iliac vein. Once we have mobilized all the tissues of the aorta and the psoas muscle, we're going to come on the right side, a counterclockwise, so the lymph nodes are removed counterclockwise. We're going to drop right down, identify the external iliac vein, and drop right down into the obturator fossa that you can see right here. Here's the external iliac vein, and we identify the accessory obturator vein right here, okay? Here is the periaortic lymph node dissection. This is the transperitoneal approach. Again, this is either open or laparoscopic technique. What you want to do is you want to reflect the small bowel cephalad, and you want to expose the peritoneum that's overlying the aorta and vena cava, okay? Now, what you want to do is identify this mesenteric bowl, and where you start your peritoneal incision window is right here is the left common iliac, and the right common iliac is right here. You're going to start right at the sacral palmatory, so here's the bifurcation. You're going to grasp two centimeter medial to where the right common iliac is, tent it up, and you're going to open the peritoneal incision, and you're going to incise this right here, and you're going to incise this peritoneum parallel along to the aorta and the vena cava, and we're opening up this peritoneal incision. Here is the mesenteric bowl, and once we open this up, the vena cava is exposed, and there is your ureter, and there is your ovarian vessel, and again, we're going to pull the lymphoid tissues off the vena cava and skeletonize it, and we're going to work, this is box number two, all the way up to where the right ovarian vein drains into the vena cava. You can see the lymph nodes here that's being removed. I usually like to use a Raytec in there, and what I do is put a Raytec under there, sort of like a lap sponge retracting, and I have the assistant basically retracting the top right there. So you have to be careful, I'm going to see, when you're using this, what this is, I left this video primarily to show you, this is the duodenum right here. Here's the seroso-denuded area, because we were using the energy, and I got a little too close right here. So once we recognize that, you've got to try to reinforce it, so we're going to reinforce this seroso-denuded area on the duodenum. And what I'm using is this sewing device, what's called the endoclose, and we basically sew it to reinforce the duodenum, and then continue on with our dissection along here. So these are the pertinent structures that you have to remember when you're performing aortic lymph node dissection. So in an open procedure technique, after you have incised this, so you've got this peritoneal edges, whatever retractor you have, you're going to have these retractors come in and retract laterally away for you, so that this is exposed. In the minimally invasive technique, we are retracting, we're using the peritoneum as the barrier, and so that's what you're seeing, and here's the cava right here that you see. Here is the ovarian vessel that's going to insert right into the vena cava, that's what we follow. And you can see that I'm retracting the lymph nodes, cephalad, away from the vessel, gingerly pull up. This is your assistant holding the left lateral edge peritoneum. If anybody have questions, you can put it in the chat form, I guess. Again, this is the aorta right here. We're removing the lymph nodes right along lateral to the cava right now. So there's the duodenum, whenever that serves as a superior boundary, as soon as we find the duodenum, your renal vein lies right under here, you can see that left renal vein right here that's coming through here, right here now. So duodenum serves as my landmark to identify the superior boundary right here. And once that's done, we start our lymph node dissection again on the box four. So you can see that the, that's the inter-aortic cable lymph nodes that we're removing. And as you come across here, you have to be very careful, make sure you seal this because this is where chylis exides can be formed if you don't seal this well, the inter-aortic lymphoid tissues here. Right here. Can you guys see my marker, my hand marker? I'm not sure that you can see that. Yes we can, I can. Okay. So again, elevate your lymphoid tissues away from the vessel and you want to, the energy is towards the lymphoid tissue, not the vessel, so that you don't get thermal injury. And we're going to go all the way up to where this is the left renal vein, you can see right there. Right here is your left renal vein. And here is the left ovarian vein inserting into the left renal vein right here. So these are the anatomical landmarks that we use to get to where we, where we need to. Here's your renal vein. And then we basically identified the left common iliac vessels. Open up this peritoneum, look for the left common iliac, and drop right down and identify drop right down and identify the left ureter, which is right there, that's attached to the medial leaf of the peritoneum right there. Once we identify that, again, your assistant holds the retractor and basically start on the left common iliac and work your way up. This is the IMA that you see right here. Here it is, the IMA. So what we do is I identify where the known structure is and just kind of work my way up and this is the box number three lymph node because the IMA is the superior boundary. And here's the left common Iliac and basically remove the left left notes here. So, this is after removal of all the lymphoid tissues in box number three. So, what do we do when you're doing lymph node dissection and you get into a bleeding. So these are some of the steps that I want you to think about and off. The very first thing you want to do is, it's very very nerve wracking if you will. When you get into being a cave of bleeding, or an aorta when you're performing when you have a vascular injury. It is for this reason, you can see that in my procedures I always have a rate tech sponge lap sponge in it. And that use, I use that in the event that if there's any bleeding now, fortunately, I haven't had to use this so I can't demonstrate I can't show you a video of it because I really haven't had that but I teach a course here and I go through this exercise with all the surgeons, you want to analyze the situation. The very first thing you want to do is one, whatever the bleeding is you obviously want to put the lap sponge. Oftentimes, if you have a small cable injury, putting a lap sponge with co2, or you basically apply pressure, it will resolve. Okay, if you're. So, and you want to analyze the situation, the nature of the injury, whether it's a vascular in terms of vein or arterial, and you want to. It's so important that you want to have adequate access. Your operative field has to be clear whether it's an open procedure or minimally invasive. If you're doing laparoscopic surgery minimally invasive, you want to be prepared. If you cannot not six if you're not successful you want to open, and you want to collect the instruments in preparation for repair and call for help, of course. And basically communication is very, very important. You have to decide how you will approach the repair, whether you're going to sell it apply him a clip or these chemo seal products. I'm sorry that I don't know that some probably a lot of the different regions, you may or may not have these chemo seal agents. They range anywhere from gelatin matrix to oxidized cellulose to micro fibular collagen. The cost is various, oftentimes, what my sequence of events is, if I have a vascular injury. The first thing I'll do is I'll apply pressure, and I will literally hold pressure. And I will look at the clock. I will apply for five minutes while everything all the instruments are gathered. It's an important thing to exercise go through and that exercise in your mind what you're going to do. While everything's gathering, you want to optimize your operative field. And once everything is appropriate. You want to then see if the pressure that you've applied. Stop the bleeding, if it doesn't stop. You're going to make a choice between you're going to either going to put a human clip, or you're going to so, or you're going to put gel foam, or these humans static agent. I don't like to use a hemostatic agent. Before I apply a clip or sewing. Because once you put the gel foaming on, you're not going to have the ability to so. So the sequence of events is you're going to apply a pressure. Then you're going to decide whether you're going to put a clip or so. If you, if that doesn't work or then you can apply the hemostatic agent. Okay. And that's what you have to remember, these are various different hemostatic agents that we have. Now what about when you're performing pelvic and periodic lymph node dissection. The risk of injuring the. This procedure is obviously you can see urinary tract injury urinary tract injury associated with pelvic surgeries everywhere been reported to 0.3 to 1%. Not very common. What about lateral injuries bladder injuries the most common because that's where mostly we're performing a hysterectomy 2.4% of patients may require urologic intervention. So what are some of the risk factors that's associated with gentle urinary. Oftentimes, it's distorted pelvic anatomy. Various different causes as you can as listed here, or poor exposure obscure of tissue points. These are the previous infectious process radiation previous surgery, the scarring that can cause. Okay. And these are the various procedures that that are puts a person at risk for your logic of potential your logic complication. What are some of the pathogenesis dissection poor handling of tissue, or you could basically crush injury. You could basically kink or ligated or lacerated or purely transaction or devastation or thermal injury. These are all the various potential causes for that you need to be cognizant. At the time of the surgery. Immediate recognition is really important, just like the laparoscopy that I showed you the duodenum. I was aware of the, the, the thermal trans transmission that denuded the cirrhosis area. As soon as I identify it, reinforce it. Okay, so immediate recognition is very important urine in the surgical fields that causes a suspicious. If you're concerned you could use indigo Carmen, if you have that, or if you have air in the Foley bag that typically represents a bladder injury that post operative injury for gentle urinary complication thermal injury. These thermal injury are typically delay manifestation, typically in between post up day seven and 14 symptoms usually associated with nausea and vomiting, they'll oftentimes come in with that with Now a lot of patients I don't know about post operatively may have nausea and vomiting, because of either narcotics or coming out of anesthesia. So you have to remember the other symptoms is a walking incontinence indicating possibly a fistula. These are physical findings that may happen present abdominal distention vaginal pooling. This is, I like to perform a methylene blue challenge test. If I'm suspecting a vesicle vaginal fistula repair, or what I call a tampon test tampon test is basically ruling out a ureteral vaginal fistula. This is something that you can do really easily, where you give a peritoneum, which is a oral medication. I don't know that if you have it in your region that often causes your urine, after you take it turns your urine orange. So typically if you're suspecting a ureteral vaginal fistula, you can put tampons in the vaginal canal and have them take the pill. The first thing you want to do is you want to rule out the, the vesicle vaginal fistula, and the way you do rule that out is you can use a methylene blue test and then backfill the bladder to see if there's any drainage coming out from the, the vagina. If you rule that out, and they're still having incontinence. You want to do what we call the tampon test and that is giving the oral form of this medicine that causes your urine to turn orange, and you put a tampon in there. If the tampon turns orange, more than likely you've got a ureteral vaginal fistula. The diagnostic evaluation is the elevated creatinine. Oftentimes, if they have fluids in the belly, you can extract the fluid by performing a paracentesis and send it off for fluid for creatinine, where elevated fluid creatinine. The serum creatinine should be the same as the fluid in the pelvic cavity, if you extract it. If you have fluid that is in the belly, and you have a urinoma when you extract that fluid, these will be paracentesis, and you sent that off for creatinine, it will often be greater than one, or your serum creatinine, and you have your diagnosis there. So prevention, primary, is anticipation. You want to do hydro distention. You want to try to use ureteral stent, if you have a difficult time, on a difficult case. Use of lighted stent, I don't know that a lot of the region will have that, and use of ICG green. These are novel techniques that can help you identify these structures. Secondary, intraoperative recognition and repair of injury. So if you're having a difficult dissection, following your dissection, you want to inspect the area that you dissect, particularly the ureters, to make sure that you haven't compromised them vascularly. If you have a potential bladder injury, oftentimes in minimally invasive surgery, because of the carbon dioxide, you'll have air in the foley catheter, which you will recognize. And tertiary prevention is postoperative diagnosis and treatment. So what I want you to remember in avoiding complication is when you're performing a minimally invasive laparoscopic procedure, an open laparoscopy should be performed. I think you've all been taught that on previous laparotomy. You want to place appropriate placement. And more importantly, you want to know your anatomy. Hopefully, this morning I've shed some light of the anatomy that's involved and associated with this procedure. You want to optimize your operative field to perform the dissection. You want to practice good surgical technique. And this is really important because you want to skeletonize the lymph node away from the vessel. Remember that. You want to cauterize on the lymphoid, the lymphatic tissue side and not the vascular side. And you want to start your dissection lateral to the vessel and not in the middle of the vessel, because you don't know what perforators are there. Because if you start your dissection in the middle of the vessel, you may get into the bleeding right away and you're going to have yourself a long, long, long day. It's important to perform your procedure repetitively and systematically, doing it the same way every time. Okay. And you want to maintain your instruments in the operative field. So in conclusion, minimally invasive surgical staging is associated with less blood loss, less pain, less complication. Ovarian cancer surgical staging requires appropriate pelvic and infarenal aortic node dissection. And laparoscopic pelvic and aortic lymph node dissection appears to be feasible for ovarian cancer. All right. I don't know if it's an hour. With that, I will conclude. Oh, one more slide. And for sentinel lymph node ICG appears to be an optimal tracer to detect sentinel lymph nodes. Sentinel lymph node in early stage endometrial cancer identifies less than 50% mild invasive or grade one is adequate for staging. In early stage intermediate and high risk appears to be safe, but more studies are needed. A full infagnectomy should be considered in the ipsilateral pelvic lymph nodes if sentinel lymph node is not identified. Okay, that's it. Thank you so much. That's an hour and five minutes. Sorry that I went five minutes over. No problem. Any questions? I think there was a question in the chat. Miriam, you had a question? Oh, yes. Let me. Okay. I didn't understand how you can do sentinel lymph node mapping in ovarian cancer staging. You don't. This sentinel lymph node mapping is not appropriate for ovarian cancer staging. I'm sorry that I didn't mean to imply that. Sentinel lymph node mapping currently as we understand it right now is in the setting for endometrial cancer only. Not for cervix or not for ovarian cancer. Thank you, Miriam. Did that answer your question? Thank you so much for a wonderful lecture today, Dr. Lim. And I have a question. Actually, we don't do the periaortic lymphadenectomy through a laparoscopic approach. We should do the vertical incisions. And so sometimes it's quite challenging with the women with their own overweight and obese women. And so can you share some tips in those women? Well, I think you have a very, very valid point because laparoscopic periaortic lymphadenectomy is exceedingly challenging for high BMI patients. Okay. My suggestions to you guys as a fellow is I wouldn't start off minimally invasive surgery. Hopefully, I know that there are a lot of videos that I've demonstrated to you. It's not to convey that that's what you should be doing. I'm using the video to demonstrate to you the anatomical relationship and how to set up the operation. It's very difficult for me to sort of videotape an open periaortic lymphadenectomy because you just can't see very well. And the takeaway message for you is understanding the anatomical boundaries and relationship. And the first thing what I want you guys, you know, I want you to be familiar with doing a periodic open procedure. Okay. And then the laparoscopic, I mean, if you have a BMI of a patient of probably 30 and above or 35 and above, it is an exceedingly challenging procedure to do laparoscopically, particularly the left side to get access to there. Okay. So that would not be the first case that I would do. I would get lots of experience first doing an open procedure. Dr. Kim asked, what do you think about the re-injection for unmapping sentinel lymph nodes? I think you can try that. I have done it in situations where I didn't feel like the mapping had really, I couldn't get a mapping. Sometimes you can re-inject it at two cc's and all to see, but if you're not going to have the, if it's not going to map, I recommend doing a lymphadenectomy for it. Thank you. You're welcome. Any other questions? Yeah. In your institute, did you use sentinel lymph nodes or replace their lymphadenectomy in high-risk uterine cancer? Do I use sentinel lymph nodes? Yes, in your institute, yeah. Okay. So let me just rephrase the question so that I understand. So I think your question is, do I rely on sentinel lymph node mapping in high-grade endometrial cancer? Yes. Okay. So I personally don't. I think, you know, Pamela, Dr. Solomon from MD Anderson did a very, very nice work on their series and they reported it. I think it's, I still rely on a full staging because of the potentially higher risk for sentinel lymph nodes. I mean, that's undetected, the false negative rate on the high-risk patients and all. So I still do a full staging for endometrial cancer that have high risk factors. Thank you, Dr. Lin. You're welcome. Any other questions? Hi, Dr. Lin. This is Vince from Uganda Cancer Institute. So you mentioned that when you don't map on one side, you do a site-specific lymphadenectomy. So my question is, if you do a site-specific lymphadenectomy, do you think that procedure then is still sentinel node procedure or you're probably looking at doing lymphadenectomy both sides? And what is your practice on that if you don't map on one side? I'm sorry, what is the what? I didn't hear you. I apologize. Sorry, my question is that you mentioned that if you don't map on one side, do you do a full lymphadenectomy on both sides or on one side that hasn't mapped? No, if the one side does not map or the unmapped side, I will do the same side that's not mapping. I don't do a complete pelvic lymphadenectomy. This is for early stage endometrial cancer. And there's lots of data right now out that I think that's adequate for sentinel lymph node mapping. So if you're not mapping it, you should do the side that's not mapped. Thank you. Any other questions? Was this helpful in terms of, you know, the anatomy for you guys? Yes, it was very helpful. Good. All right. Good. I'm glad that that was helpful. Well, thank you for the opportunity. I wish you all have a, I think you guys are Saturday, it's 10-15pm here and Susan is bedtime for her. So thank you so much, Susan. No problem. And I appreciate it and I will see you all a different time. Wonderful. Thank you so much, Dr. Lim. Thank you, everyone. Thank you. Okay, bye bye. Bye.

surgical staging

gynecological cancer

indications

complications

anatomy

technique

sentinel lymph node technology

pelvic lymph node dissection

aortic lymph node dissection

endometrial cancer staging

operative field