Pelvic Lymphadenectomy





This chapter describes the operative steps to performing an open bilateral pelvic lymphadenectomy as part of a radical cystoprostatectomy and anterior exenteration. The laparoscopic approaches to the pelvis and pelvic lymph nodes are discussed in other chapters.


The limits of dissection can be bound superiorly at several different levels, including at the bifurcation of the common iliac arteries, at the bifurcation of the aorta, or at the level of the inferior mesenteric artery (IMA) with or without inclusion of the presacral lymph nodes. The technique described herein is the maximum extent described in the literature, which is to the IMA with inclusion of the presacral lymph nodes. The approach can be modified as needed if the upper bound of dissection is lower.


Lymphadenectomy in the Male


The patient is generally in the supine position. The patient is modestly flexed at the hip. If desired, the kidney rest can be positioned at the level of the sacrum and raised. The patient is then prepped and draped sterilely. A Foley catheter is sterilely placed in the bladder from the operative field after the patient is draped.


Midline incision is made from the level of the symphysis pubis to the level approximately 2 cm cephalad of the umbilicus. The incision should traverse around the umbilicus on the side opposite the stoma marking ( Fig. 51.1, A ). If the patient has elected to undergo a continent cutaneous diversion or if this is a possibility and the umbilicus is to be the stoma site for the afferent limb, then be sure to stay wide of the umbilicus and preserve the fascia in that area. If a more limited pelvic lymphadenectomy is anticipated (e.g., to the level of the bifurcation of the common iliac arteries), then the incision can go superiorly to just below the umbilicus rather than around and above it. Divide the subcutaneous tissues down to the level of the fascia, which is divided in the midline. As with the incision, if a continent cutaneous diversion is a possibility and the umbilicus is to be used as the stoma site, then the periumbilical fascia should be preserved.




FIGURE 51.1


Lymphadenectomy in a male patient. ( A ) Midline incision. ( B ) Ligate and divide the urachus.


Enter the peritoneum in the midline above the umbilicus. Open the peritoneum superiorly. Ligate and divide the urachus ( Fig. 51.1, B ). Incise the peritoneum inferiorly laterally to the medial umbilical ligaments bilaterally. Be sure not to incise too far lateral and injure the inferior epigastric vessels. At this point, the incision of the peritoneum need only be carried inferiorly to approximately the level of the confluence of the vas deferens and spermatic chord bilaterally.


Explore the abdominal contents. Start in the right paracolic gutter, move superiorly, palpating the anterior and posterior aspects of the liver. Palpate the stomach. If a nasogastric tube has been placed and is to remain postoperatively, its proper position in the stomach can be verified now. Continue left and inferiorly, palpating the retroperitoneal nodes overlying the great vessels and the left pericolic gutter. Continue inferiorly and assess the resectability of the bladder (i.e., ensure it is not fixed to the pelvic side wall or rectum).


Retract the divided urachus inferiorly, which partially mobilizes the bladder out of the pelvis ( Fig. 51.2, A ). Begin dissection by mobilizing the cecum along the white line of Toldt and dissecting the root of the small bowel mesentery off the retroperitoneum cephalad. This should go no farther than the level at which the third portion of the duodenum is identified. Attention is turned to the left side, where the left colon and sigmoid colon are mobilized off the left pelvic side wall and retroperitoneum, starting again at the white line of Toldt on that side.




FIGURE 51.2


Lymphadenectomy in a male patient. ( A ) Retract the divided urachus inferiorly. ( B ) Dissection of left ureter.


A plane is developed between the root of the sigmoid mesentery and the sacral promontory by gently passing the surgeon’s hand between this space, starting on the left side of the root of the sigmoid mesentery and passing to the right. The overlying peritoneum on the right is divided, extending into the pelvis inferiorly and superiorly to the level of the IMA. A self-retaining retractor may be placed if desired. Retractor blades would be placed on the body wall bilaterally as well as superiorly to retract the small bowel and cecum, which are packed with open moist laparotomy sponges. The sigmoid colon should be left mobile and not retracted with the self-retaining retractor blades.


Begin dissection of the right ureter by identifying it as it traverses anterior to the right common iliac artery. Dissect the ureter down into the pelvis, being sure to include sufficient periureteral tissue to ensure adequate blood supply. The dissection should continue approximately 2 to 3 cm beyond the common iliac artery. The ureter should be ligated and divided at this point. The proximal end may be sent for frozen section. The ureter is then dissected superiorly, focusing mainly on dividing its medial attachments, leaving the tissue between it and the spermatic chord laterally as intact as possible. The ureter is then packed in a moist sponge and placed in a pocket in the retroperitoneal space posterior to the retracted cecum and small bowel. The sigmoid colon is retracted to the right. The left ureter is dissected in essentially the identical fashion, continuing at least 2 to 3 cm into the pelvis beyond, where the ureter passes over the left common iliac artery ( Fig. 51.2, B ). It is ligated and divided, and the proximal end may be sent for frozen section analysis. It is dissected superiorly, again focusing mainly on dividing the medial attachments to preserve the blood supply in the tissue between it and the spermatic chord laterally. The ureter is again wrapped in a moist sponge and packed in the retroperitoneal space posterior the retracted small bowel and left colon.


With the sigmoid colon and mesentery still retracted to the right, incise the tissue lying just lateral to the left common iliac artery starting at the bifurcation of the common iliac artery and moving superiorly, bearing in mind the lateral border of dissection is the genitofemoral nerve. Continue the dissection cephalad, sweeping the lymphatic tissue inferiorly and medially off the anterior aspect of the left common iliac artery and then lower aorta up to the level of the IMA ( Fig. 51.3, A ). This will require at some point retracting the sigmoid colon and its mesentery to the left laterally, either with a hand or with a retractor blade placed in the space created earlier anterior to the sacral promontory. At the level of the IMA, dissect to the right, sweeping the lymphatic tissue off the anterior surface of the lower aorta and inferior vena cava using hemoclips along the superior border of dissection. When the right genitofemoral nerve is reached, this is the lateral limit of dissection on the opposite side. Dissection now proceeds inferiorly, sweeping the lymphatic tissue off the anterior surface of the right common iliac artery to the level of the bifurcation of the common iliac artery on the right.




FIGURE 51.3


Lymphadenectomy in a male patient. ( A , B ) Sweeping of the lymphatic tissue.


Sweep the lymphatic tissue off the anterior surface of the right common iliac artery and continue along the medial surface of the artery until the left common iliac vein is identified ( Fig. 51.3, B ). Divide the lymphatic tissue over the left common iliac vein and sweep this inferiorly in conjunction with the tissue off the medial most aspect of the right common iliac artery down to the level of the sacrum. Identify, ligate, and divide the one or two middle sacral veins that enter into the left common iliac vein. Sweep the lymphatic tissue off the sacral promontory using hemoclips as needed. Once the lymphatic tissue has been removed, a Ray-Tec sponge may be placed in this space and removed later after the bladder is excised.


Turn attention now to the left hemipelvis. The sigmoid colon should be retracted to the right. A finger is placed in the space of Retzius and passes cephalad, mobilizing the bladder medially off the pelvic side wall ( Fig. 51.4, A ). Almost simultaneously, pass a finger from the opposite hand anterior to the iliac artery starting at the cut edge of the peritoneum, medial to the spermatic chord, and passing caudally. The fingers meet each other, and the bladder is retracted medially. The peritoneal reflection is now divided, being careful to avoid injury to the spermatic chord until the vas deferens is isolated. This is now ligated and divided.




FIGURE 51.4


Lymphadenectomy in a male patient. ( A ) Mobilizing the bladder medially off the pelvic side wall. ( B ) Division of the lymphatic tissue over the external iliac vein.


At this point, the external iliac vessels should be well exposed. Divide the lymphatic tissue over the external iliac vein and sweep this medially ( Fig. 51.4, B ). Dissect the tissue just distal to the lymph node of Cloquet, which represents the inferior limit of dissection. Hemoclips should be used at the inferior border of dissection. Mobilize the lymphatic tissue now off the lower aspect of the pelvic side wall posteriorly to the level of the obturator vessels and nerve. Be alert for an accessory obturator vein, which should be ligated and divided if encountered.


Divide the lymphatic tissue overlying the external iliac artery and in a split and roll fashion isolate this vessel and retract it medially. Mobilize the lymphatic tissue medial to the genitofemoral nerve off the pelvic side wall using hemoclips as necessary for perforating vessels. The remaining lymphatic tissue lying over the external iliac vein is now divided with the external iliac artery retracted medially.


Use a Ray-Tec sponge that has been opened and pass this in the space lateral to the external iliac vessels, starting at the level of the bifurcation of the iliac artery and passing inferiorly and posteriorly into the obturator fossa ( Fig. 51.5, A ). This will sweep all the lymphatic tissue into the obturator fossa. The lymphatic packet is now retracted medially, and any remaining attachments to the external iliac vein can be divided. Dissect free the obturator nerve, which is now retracted superiorly along with the external iliac vein with a vein retractor. Isolate the obturator artery and vein as they egress the pelvis at the obturator foramen. Ligate and divide these vessels, which will allow the entire lymph node packet to be retracted medially out of the obturator fossa (see Fig. 51.5, B ). It can now be removed separately or keep attached with the bladder to be removed en bloc.




FIGURE 51.5


Lymphadenectomy in a male patient. ( A ) Sweep the lymphatic tissue into the obturator fossa. ( B ) Ligation and division of the lateral pedicle.


At this point, the lateral pedicle of the bladder on the left side can be readily isolated and divided as per the radical cystectomy. If the bladder is not going to be removed, then the lymph node packet can be removed at this point.


The previous two steps are now repeated in mirror image on the right hand side. Again, as in Fig. 51.5, B , after the lymph node packet has been retracted medially and the obturator vessels ligated and divided, the lateral pedicle of the bladder is well exposed and can be ligated and divided as per the radical cystectomy. Otherwise, the lymph node packet can be removed, drains placed, and the incision closed after ensuring good hemostasis.




Lymphadenectomy in the Female Pelvis


The pelvic lymphadenectomy in the female patient is similar to that in male patients, but certain specific differences warrant attention. One is the positioning of the patient, which in a female patient is either in a frog-leg position (ensuring good support at the knees) or in a low lithotomy position, depending on the surgeon preference and the size and location of the tumor.


In male patients, the spermatic chord is preserved, and dissection proceeds medial to these structures. In female patients, the infundibulopelvic ligament is identified, ligated, and divided before beginning dissection of the ureter into the pelvis ( Fig. 51.6 ). In addition, the round ligament rather than the vas deferens will be the structure that is divided after the bladder has been mobilized off the pelvic side wall.


Jan 2, 2020 | Posted by in UROLOGY | Comments Off on Pelvic Lymphadenectomy
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