Gynecologic Oncology: Clinical Practice and Surgical Atlas, 1st Ed.

Lymphadenectomy

Lisa A. dos Santos and Nadeem R. Abu-Rustum

INTRODUCTION

Surgical staging including lymph node dissection is the cornerstone of treatment of early-stage endometrial and ovarian malignancies. In 1988, surgical staging replaced clinical staging for endometrial cancer, due to inherent underreporting of metastatic disease distribution in the clinical staging system. Comprehensive staging guides treatment planning for subsequent chemotherapy and/or radiation therapy. In the setting of advanced or recurrent disease, lymph node dissection may be undertaken for the purpose of removing bulky tumor. Although cervical cancer is staged clinically, lymph node dissection plays a role in the management of early-stage tumors.

The lymphatic drainage of the uterus, tubes, and ovaries follows the blood supply of these organs and includes the pelvic lymph node basins as well as the aortic lymph nodes (Figure 28-1). Depending on the site of malignancy and the clinical indications, lymph node dissection may be undertaken in some or all of these basins, either unilaterally or bilaterally.

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FIGURE 28-1. Pelvic and aortic lymph node basins. (Redrawn, with permission, from Chi DS, Bristow RE, Gallup DG. Surgical principles in gynecologic oncology. In: Barakat RR, Markman M, Randall ME, eds. Principles and Practice of Gynecologic Oncology. Baltimore, MD: Lippincott Williams & Wilkins; 2009:270.)

PELVIC LYMPH NODE DISSECTION

Procedure Overview


Box 28-1 Master Surgeon’s Corner

images Adequate exposure and identification of anatomic structures are crucial to avoid injury to adjacent structures of the pelvic sidewall.

images Proper development of the paravesical and pararectal spaces is an essential step prior to beginning the process of removing lymph nodes.

images Appropriate use of hemostatic clips and vesselsealing devices (ie, limiting the use of monopolar cautery and blunt dissection) may reduce the risk of lymphorrhea.


Indications and Historical Perspective

There is a generalized lack of standardization in the technique of pelvic lymphadenectomy in gynecologic cancer that is apparent in both the literature and surgical practice. With the exception of sentinel lymph node mapping, the total number of lymph nodes removed is most often used as a surrogate for the radicality and completeness of the procedure. Cibula and Abu-Rustum1 recently attempted to clarify and standardize the terminology and anatomic basis for the procedure, proposing a new anatomically based classification system for pelvic lymphadenectomy. In this system, a complete systematic lymphadenectomy or “type III dissection” includes the removal of all fatty lymphatic tissue from the predicted areas of high incidence of lymph nodes with metastatic involvement. This comprehensive procedure is described later in this chapter and includes dissection of the 5 main anatomic regions of the pelvic lymphatic drainage: external iliac, obturator, internal iliac, common iliac, and presacral lymph nodes. In certain circumstances, more limited dissection may be indicated, such as sentinel lymph node biopsy, excision of only bulky nodes, or lymph node sampling.

Several operative approaches may be used for the pelvic lymph node dissection. It is often performed via laparotomy at the time of open hysterectomy or laparoscopically at the time of total laparoscopic hysterectomy or laparoscopic-assisted vaginal hysterectomy. In some cases, it is performed as part of a secondary staging procedure, which often may be accomplished laparoscopically. In addition, the technique of pelvic sentinel lymph node mapping may be used in selected cases. The equipment required varies by the operative approach, as described later.

Preoperative Preparation

Patient Evaluation and Work-Up

Prior to surgery, the patient should undergo a complete history and physical, complete blood count, basic metabolic panel, coagulation profile, pregnancy test, electrocardiogram, and chest radiograph (when indicated by the patient’s age).

Consent Considerations

In addition to the standard risks of general anesthesia and abdominal surgery, a discussion of procedure-specific risks is warranted, including chronic lymphedema, lymphocele potentially requiring further medical or surgical treatment, and injury to adjacent nerves, vascular structures, and the ureter.

Patient Preparation

A preoperative bowel preparation may be helpful to decompress the bowel and facilitate exposure. Epidural anesthesia may be offered for open procedures, which may optimize postoperative pain control while reducing the adverse effects of intravenous opioid analgesia. As with any open procedure, a single dose of prophylactic antibiotics should be administered intravenously within 60 to 120 minutes of the initial skin incision.

Operative Procedure


Box 28-2 Caution Points

images Careful placement of lateral retractors without exertion of excessive pressure on the psoas muscle will avoid potential injury to the femoral nerve.

images Careful identification of the genitofemoral and obturator nerves is essential to avoid injury, and the use of electrocautery should be minimized in close proximity to these fine nerve structures.

images Retraction on the external iliac vein during the obturator dissection must be applied gently to avoid intimal injury and minimize the risk of subsequent deep vein thrombosis.

images Careful dissection is particularly important in the obturator space to avoid bleeding from the corona mortis.


Open Pelvic Lymph Node Dissection

The procedure may be performed in the supine position, although it is usually combined with hysterectomy requiring the dorsal lithotomy position. A Foley catheter is placed. While a pelvic lymph node dissection may sometimes be adequately performed through an extended transverse incision (eg, Maylard or Cherney), maximal exposure is obtained with a vertical midline approach, particularly in the obese patient or if dissection of the deep common iliac lymph nodes is required. Standard laparotomy equipment is required for an open dissection, including a self-retaining retractor (eg, Bookwalter). In addition to standard instrumentation, Penfield dissectors may be useful in cases with adherent lymphadenopathy (Figure 28-2).

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FIGURE 28-2. Penfield dissectors.

Opening the Pelvic Peritoneum

The round ligament is clamped and divided, and the umbilical ligament is isolated. Working parallel to the round ligament, the peritoneum is incised with Metzenbaum scissors or electrocautery in a linear fashion between the round ligament and the umbilical ligament to the reflection of the anterior abdominal wall.

Development of the Paravesical Space

The umbilical ligament is retracted medially to facilitate blunt dissection of the paravesical space, exposing the external iliac nodes, obturator space, and ventral aspect of the hypogastric vessels.

Identification of the Ureter

The ureter should be clearly identified as it crosses the bifurcation of the common iliac artery into the internal and external iliac artery, and courses along the medial leaflet of the broad ligament. A vessel loop may be placed around the ureter for gentle retraction and continued identification throughout the procedure.

Development of the Pararectal Space

The peritoneal incision is extended cephalad along the psoas muscle, lateral and parallel to the infundibulo-pelvic ligament. Next, the infundibulopelvic ligament (if not already divided) and ureter are retracted medially, and the hypogastric artery is identified. The pararectal space is then developed bluntly, retracting the rectum medially and providing access to the hypogastric nodes and obturator space.

External Iliac Lymph Node Dissection

The dissection begins with the external iliac lymph nodes. A Singley (ringed) forceps may be used to gently grasp the lymphatic tissue without fracturing the nodes. Sharp or blunt dissection with Metzenbaum scissors is used to isolate small blood vessels and lymphatic channels, which are secured with hemostatic clips and divided. The lateral border of the dissection is the genitofemoral nerve. Moving from lateral to medial, the nodal tissue is dissected first from the psoas muscle and then the external iliac vessels, taking care to protect the genitofemoral nerve and the external iliac artery and vein. The cephalad limit of the external iliac dissection is the bifurcation of the common iliac artery, and the caudal limit is the deep circumflex iliac vein, a branch of the external iliac vein that is usually seen coursing anteriorly over the external iliac artery. Lymph nodes caudal to the deep circumflex iliac vein predominantly drain the lymphatics of the lower extremity, and their removal may increase the risk of lymphedema.

Obturator and Hypogastric Lymph Node Dissection

The obturator and hypogastric lymph nodes may be accessed from a medial or a lateral approach, and many surgeons use a combined approach. Beginning with a medial approach, the external iliac vein is gently pulled laterally with a vein retractor, and the nodal package posterior to the vein is grasped with the Singley forceps. Gentle dissection is used to identify the obturator nerve, and the nodal package between the vein and nerve is dissected free. Next, additional nodes may be removed from below the nerve. Care should be taken to avoid injury to the obturator vessels and anastomotic obturator or pubic veins, which may sometimes be encountered in the distal portion of the obturator space. This area has been referred to as the “corona mortis,” or ring of death, due to the potentially treacherous plexus formed by variable anastomotic veins that are often found linking the obturator and external iliac venous systems. A 4-part “ring” may be formed by the external iliac vein, hypo-gastric vein, obturator vein, and anastomotic obturator or pubic vein (Figure 28-3).

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FIGURE 28-3. Corona mortis. The anastomotic obturator or pubic vein is seen crossing the distal obturator space and entering the left external iliac vein.

The hypogastric nodes may then be dissected from the proximal portion of the umbilical ligament, moving cephalad over the hypogastric artery and the origin of the uterine artery. Finally, the external iliac vessels are bluntly mobilized medially from the psoas muscle, allowing access to the obturator space from a lateral approach, to remove any remaining nodal tissue from behind and beneath the vessels, particularly near the common iliac artery bifurcation.

Common Iliac Lymph Node Dissection

In a type III pelvic lymph node dissection as described by Cibula and Abu-Rustum,1 the common iliac dissection includes removal of the superficial and deep common iliac lymph nodes. The common iliac lymph nodes receive lymphatic vessels from 2 major lymphatic trunks draining the uterus and cervix. A superficial trunk enters the pelvis via the femoral canal, courses along the ventral aspect of the external iliac vessels, receives branches from the parametrium, and continues along the ventral aspect of the common iliac artery (Figure 28-4). On the right side of the pelvis, these lymphatics continue toward the precaval and interaortocaval regions; on the left side of the pelvis, they continue to the left para-aortic region.

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FIGURE 28-4. Pelvic lymphatic drainage: the superficial lymphatic trunk. (Redrawn, with permission, from Cibula D, Abu-Rustum NR. Pelvic lymphadenectomy in cervical cancer: surgical anatomy and proposal for a new classification system. Gynecol Oncol. 2010;116:33-37.)

A deep trunk also enters the pelvis via the femoral canal but follows a more medial course, surrounding the obturator nerve and receiving parametrial lymphatics before entering the common iliac area (Figure 28-5). This deep trunk then divides into 2 branches. A lateral branch courses between the common iliac vein and the psoas muscle, forming the deep common iliac nodes before entering the paracaval region. A medial branch tunnels beneath the common iliac vessels to the medial aspect of the vessels and enters the presacral area, forming the presacral nodes, before coursing toward the interaortocaval and preaortic regions.

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FIGURE 28-5. Pelvic lymphatic drainage: the deep lymphatic trunk. (Redrawn, with permission, from Cibula D, Abu-Rustum NR. Pelvic lymphadenectomy in cervical cancer: surgical anatomy and proposal for a new classification system. Gynecol Oncol. 2010;116:33-37.)

The common iliac dissection begins with careful removal of the superficial common iliac lymph nodes from the ventral and lateral surfaces of the common iliac artery and vein. Next, the deep common iliac lymph nodes (formed by the lateral branch of the deep lymphatic trunk) are identified between the common iliac vein and the psoas muscle. These are carefully removed. The cephalad limit of the dissection is the aortic bifurcation, and the lateral border is the psoas muscle. The floor of the dissection will expose the lumbosacral trunk and the obturator nerve.

Presacral Lymph Node Dissection

The presacral lymph nodes are found on the anterior surface of the sacrum between the common iliac veins and receive lymphatics from the medial branch of the deep lymphatic trunk. These lymph nodes are carefully removed, with particular care taken to avoid injury to the left common iliac vein.

Laparoscopic Transperitoneal Pelvic Lymph Node Dissection

The patient is placed in the dorsal lithotomy position with the legs placed in Allen stirrups. A Foley catheter is inserted, and an orogastric tube is placed by the anesthesiologist to provide gastric decompression. After initial trocar placement, the patient is placed in steep Trendelenburg position. Suggested equipment for the laparoscopic approach includes a 10-mm blunt port, two 5-mm trocars, a 5/10-mm trocar, 5- and 10-mm laparoscopic clip appliers, 5-mm graspers, and a 10-mm lymph node spoon. For dissection, we use a monopolar cautery device; a vessel-sealing device is also used. The procedure may be performed using a variety of available monopolar cautery devices for dissection and a vessel-sealing device.

Trocar Placement

Using an open laparoscopy technique, a blunt 10-mm trocar is placed in the umbilicus, and the abdomen is insufflated (Figure 28-6). Under direct visualization, two 5-mm trocars are placed in the right and left lower quadrants, at a point approximately 1 cm superior to and 1 cm medial to the anterior superior iliac spine. Care should be taken to avoid injury to the inferior epigastric vessels. A 5/10-mm trocar is placed in the suprapubic area, carefully avoiding injury to the bladder. Individual trocar size and placement may vary depending on planned concurrent procedures, choice of instrumentation, the patient’s habitus, and prior surgical history.

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FIGURE 28-6. Trocar placement for laparoscopic pelvic and aortic lymph node dissection. (Redrawn, with permission, from Abu-Rustum NR, Sonoda Y. Transperitoneal laparoscopic staging with aortic and pelvic lymph node dissection for gynecologic malignancies. Gynecol Oncol. 2007;104[suppl]:S5-S8.)

Development of the Paravesical Space

Using the surgeon’s chosen instrument, the round ligament is divided, and the umbilical ligament is isolated. Working parallel to the umbilical ligament, the peritoneum is incised in a linear fashion between the round ligament and the umbilical ligament to the reflection of the anterior abdominal wall. Gentle medial traction is then applied to the umbilical ligament, and the paravesical space is developed with a blunt instrument.

Development of the Pararectal Space

The ureter should be clearly identified as it crosses the bifurcation of the common iliac artery and courses along the medial leaflet of the broad ligament. The peritoneal incision is extended cephalad along the psoas muscle, parallel to the infundibulopelvic ligament. Next, the infundibulopelvic ligament (if not already divided) and ureter are retracted medially, the hypogastric artery is identified, and the pararectal space is developed bluntly, retracting the rectum medially and providing access to the hypogastric nodes and obturator space.

External Iliac Lymph Node Dissection

The dissection begins with the distal common iliac lymph nodes, lateral to the common iliac artery, and moving caudal to the external iliac lymph nodes. Laparoscopic graspers are used to protect the ureter medially and provide gentle traction on the nodal package. The monopolar cautery device may be used as both a blunt dissector and a cautery device to isolate small blood vessels and lymphatic channels, which are secured with hemostatic clips and divided. Larger vessels may be transected with a vessel-sealing device. Moving from lateral to medial, the nodal tissue is dissected first from the psoas muscle and then the external iliac vessels, taking care to protect the genitofemoral nerve and the external iliac artery and vein. The caudal limit of the dissection is the deep circumflex iliac vein, a branch of the external iliac vein that is usually seen coursing anteriorly over the artery. The nodes may be removed atraumatically from the abdomen using a 10-mm laparoscopic spoon.

Obturator and Hypogastric Lymph Node Dissection

The obturator nodal package, located posterior to the external iliac vein, is grasped gently and retracted medially. Gentle blunt dissection is used to identify the obturator nerve, and the nodal package between the vein and nerve is dissected free, using clips and cautery as necessary to divide small vessels and lymphatics. Additional nodes may be removed from below the nerve, taking extreme care to avoid injury to the obturator vessels and potential anastomotic pelvic veins, which may sometimes be encountered in the distal portion of the obturator space. The hypogastric nodes may then be dissected from the proximal portion of the umbilical ligament, near the origin of the uterine artery. Finally, the iliac vessels are gently dissected medially off of the psoas muscle, allowing lateral access to the obturator space to remove any residual nodal tissue. The specimen is removed using the laparoscopic spoon.

The completed dissection of the pelvis exposes the ureter, medial aspect of the external iliac vessels, ventral aspect of the hypogastric vessels, and superior part of the obturator space, exposing the obturator vessels and nerve (Figure 28-7).

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FIGURE 28-7. Completed laparoscopic pelvic lymph node dissection. The completed dissection of the right pelvis exposes the ureter, medial aspect of the external iliac vessels, ventral aspect of the hypogastric vessels, and superior part of the obturator space, exposing the obturator vessels and nerve.

Sentinel Lymph Node Mapping and Dissection

The technique of sentinel lymph node mapping in early-stage cervical and uterine malignancy may be used in selected cases.2 A cervical blue dye injection is administered in the operating room prior to beginning the case. This may be performed at the time of examination under anesthesia, or it may be performed after skin preparation and draping. Although methylene blue 1% solution may be used, we generally use isosulfan blue 1% (Lymphazurin), a sterile aqueous solution packaged in 5-mL vials that requires no refrigeration or special preparation. Mild adverse reactions to isosulfan blue may occur in a small number (< 1%) of patients, consisting of localized swelling or pruritus of the neck, abdomen, hands, or feet. Severe anaphylactic reactions are rare but have been reported with similar compounds. Use is contra-indicated in patients with a known hypersensitivity to phenylethane compounds. A transient idiosyncratic decrease in the pulse oximeter reading is common immediately after the injection and represents detection of the blue dye in the circulation rather than actual hypoxemia. Blue-tinged urine is frequently noted for up to 24 hours after surgery.

The cervical injection may be performed with a spinal needle, and a tenaculum placed on the anterior lip of the cervix may be used for traction. A total of 4 mL of blue dye is injected into the cervical stroma, with 2 mL injected at each of the 3 o’clock and 9 o’clock positions. It is important to inject the dye into the cervical stroma, with approximately 1 mL injected deeply and 1 mL injected superficially. This approach avoids excessive staining of the bladder flap and targets the parametrial lymphatic drainage. If gross cervical tumor is present, the dye should be injected into the cervical stroma adjacent to the lesion.

The procedure then continues as planned, either via laparoscopy or laparotomy. The lymph node mapping is usually visible transperitoneally upon entering the pelvis, and the sentinel lymph node dissection is then performed in an expeditious manner to avoid excessive dissipation of the dye. The pelvic sidewalls are opened in the usual manner, the ureter is identified, and the paravesical and pararectal spaces are developed. Blue lymphatic channels are often seen coursing along the uterine vessels and crossing the hypogastric artery before draining into the external iliac and hypogastric lymph nodes (Figure 28-8). The first blue node noted along the drainage pathway is removed and designated as the sentinel node. Additional blue nodes may sometimes be identified and designated as secondary sentinel lymph nodes.

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FIGURE 28-8. Pelvic sentinel lymph node mapping. A sentinel right external iliac lymph node is identified in the usual location medial to the external iliac vessels and ventral to the hypogastric vessels.

AORTIC LYMPH NODE DISSECTION

Procedure Overview


Box 28-3 Master Surgeon’s Corner

images The goal of the operation is to remove all lymphatic tissue from around and between the abdominal aorta and IVC, which can only be accomplished by first exposing and isolating these vessels and securing control of the surrounding vasculature.

images Familiarity with potential variations in vascular anatomy of the retroperitoneum facilitates safe dissection.

images Using the ventral surface of the aorta as the midline, a “split-and-roll” technique is used to define and dissect the lateral aortic nodes in a medial to lateral fashion.


Indications and Historical Perspective

Dissection of the aortic lymph nodes is often indicated in the surgical staging of endometrial, cervical, and ovarian malignancies, as well as in cases of clinically apparent adenopathy and recurrent disease. In the staging of endometrial and cervical cancer, the dissection is generally carried to the level of the inferior mesenteric artery (IMA). In ovarian cancer, the cephalad limit of dissection is generally the renal vessels. The extent of dissection in a particular case is individualized. The technique of complete open retroperitoneal lymph node dissection is described later in this section. In some cases, such as staging of endometrial and cervical cancer, a more limited dissection may be performed.

Three surgical approaches may be used. Open dissection is used in cases where there are other indications for laparotomy (eg, concurrent procedures, extensive adhesions, patient habitus) or when a complete retroperitoneal lymph node dissection is indicated. In appropriately selected patients, transperitoneal laparoscopic aortic dissection may be used. A third approach is laparoscopic extraperitoneal dissection, which combines the benefits of laparoscopy with those of extraperitoneal dissection (feasibility despite intraperitoneal adhesions and decreased risk of bowel injury and future adhesion formation). This approach is most commonly used in the surgical staging and treatment planning of patients with locally advanced cervical cancer but may be used in other select patients as well.

Preoperative Preparation

Considerations for preoperative preparation are similar to those listed for a pelvic lymph node dissection. In cases where a complete retroperitoneal lymph node dissection to the level of the renal vessels is planned, bowel preparation is essential to provide adequate bowel decompression in order to achieve optimal exposure. In cases where a laparoscopic extraperitoneal lymph node dissection is planned, preoperative imaging should be performed to evaluate the retroperito-neal vascular anatomy, because correct identification of anatomic landmarks with limited exposure is particularly crucial to the success and safety of the procedure.

Operative Procedure


Box 28-4 Caution Points

images Limit monopolar cautery and blunt dissection in lymphatic basins to decrease lymphorrhea, chylous ascites, and lymphocyst formation.

images In a complete retroperitoneal dissection, meticulous identification and control of the lumbar vessels is essential to avoid potential hemorrhage.

images Meticulous use of hemostatic clips is particularly important around the left renal vein to secure the prominent lymphatics in that region.

images In a laparoscopic extraperitoneal lymph node dissection, it is crucial to avoid premature perforation of the peritoneum at the beginning of the procedure and to fenestrate the peritoneum at the conclusion of the procedure.


Open Aortic Lymph Node Dissection

Anatomy of the Retroperitoneum

A thorough anatomic understanding of the lymphatic drainage surrounding the aorta and inferior vena cava (IVC) will guide the extent of necessary dissection and facilitate lymph node removal while avoiding injury to adjacent structures (Figure 28-9). The aortic lymph nodes may be generally divided into 3 subgroups. The preaortic nodes drain the gastrointestinal tract to the level of the midrectum. The lateral aortic nodes (right and left) drain the iliac systems and therefore the pelvic viscera. The retroaortic nodes do not drain a particular area. Hence, the lateral aortic lymph nodes are most relevant to the staging and treatment of gynecologic malignancies. There are typically 15 to 20 lateral aortic nodes per side. These occupy the space bordered by the aorta medially, the medial aspect of the psoas muscle laterally, the lumbar spine posteriorly, the diaphragmatic crura cephalad, and the aortic bifurcation caudad.

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FIGURE 28-9. Lymphatic anatomy of the retroperitoneum. (Redrawn, with permission, from Zivanovic O, Abu-Rustum NR, Sheinfeld J. Retroperitoneal lymph node dissection. In: Levine DA, Barakat RR, Abu-Rustum NR, eds. Atlas of Procedures in Gynecologic Oncology. London, UK: Informa Healthcare; 2008:118, Figure 6.1.)

In the staging of endometrial and cervical cancer, the lateral aortic nodes are usually dissected to the level of the IMA. This artery arises from the anterior aspect of the aorta approximately 3 to 4 cm above the aortic bifurcation and provides perfusion to the descending colon and rectum. Caudal to the IMA, several pairs of lumbar arteries arise from the posterolateral surface of the aorta. The middle sacral artery arises from the posterior surface of the aorta just above the bifurcation.

The lymphatic drainage of the ovaries courses along the ovarian vessels toward their origin from the aorta approximately 5 to 6 cm above the bifurcation and 2 to 3 cm below the renal vessels. Therefore, the surgical staging of ovarian cancer requires dissection of the lateral aortic nodes from the aortic bifurcation cephalad to the level of the renal vessels. The ovarian arteries cross the ureters as they course toward the pelvis. Anomalies of the uterine arteries are not uncommon, and they may arise from aberrant locations of the aorta or directly from the renal arteries. The renal arteries arise from the aorta at the level of L2. The right renal artery normally crosses dorsal to the IVC.

The venous drainage of the para-aortic area is also variable and must be carefully identified to avoid unnecessary hemorrhage. The right ovarian vein most commonly inserts directly into the IVC approximately 1 cm below the right renal vein, but may insert into the right renal vein. The left ovarian vein follows a course close to the ureter and inserts into the left renal vein. Several pairs of lumbar veins insert into the IVC and may drain into additional ascending lumber veins that drain into the left renal vein. The left renal vein normally crosses beneath the superior mesenteric artery and ventral to the aorta to insert into the IVC. The renal veins drain into the IVC at the level of L2.

Procedure

A complete retroperitoneal lymph node dissection requires a midline abdominal incision extending from the pubic symphysis to the xiphoid process. The falciform ligament is ligated, divided, and excised to facilitate exposure and wound closure. Abdominal wall retraction may be accomplished with a self-retaining retractor such as the Bookwalter. For optimal exposure, we use 2 Balfour-type retractors, 1 placed in the pelvis and 1 placed in the abdomen, combined with a Goligher-type retractor positioned over the patient’s head and used to gently retract the exteriorized bowel. The goal of the operation is to remove all lymphatic tissue from around and between the abdominal aorta and IVC, which can only be accomplished by first exposing and isolating these vessels and securing control of the surrounding vasculature.

Exposing the Retroperitoneum. The dissection begins on the right side, with incision of the peritoneum overlying the right common iliac artery. This may be an extension of the pelvic lymph node dissection, or it may be performed first. A right angle clamp or forcep is used to elevate the peritoneum, and the peritoneum is incised with Metzenbaum scissors or electrocautery. The ureter should be clearly identified as it courses lateral to the vena cava and crosses the bifurcation of the common iliac artery into the internal and external iliac artery; it should be retracted laterally. The peritoneal incision is carried cephalad to the duodenum, which is mobilized superiorly to expose the left renal vein. The left ureter is mobilized bluntly and retracted laterally. Sharp and blunt dissection is then used to dissect the avascular plane lateral to the root of the mesentery, until the third portion of the duodenum is reached at the ligament of Treitz.

The small bowel and right colon are then mobilized. This is accomplished by incising the white line of Toldt along the right paracolic gutter and using sharp and blunt dissection to lift the right colon and small bowel off of the right renal fascia. Next, the fibroadipose tissue anterior to the left renal vein and between the undersurface of the duodenum and pancreas is clipped and divided. Completing this process allows adequate exposure to the retroperitoneum, as the small and large bowel may then be elevated and exteriorized, covered with moist laparotomy sponges, and placed on the chest. Two wide Deaver-type retractors can be attached to the Goligher-type retractor and used to gently hold the bowel in place on the chest wall, taking care not to place excessive traction.

The bilateral ureters are then identified and gently retracted laterally with vessel loops. Blunt dissection is used to develop a plane between the left colon mesentery and the left aortic lymphatic tissue. The right ovarian vessels are identified, and the right ovarian vein is ligated and divided at its insertion into the vena cava. The right ovarian artery is ligated and divided at its origin from the right anterior surface of the aorta.

Right Aortic Lymph Node Dissection. Using sharp and blunt dissection with Metzenbaum scissors, the lymphatic tissue overlying the right common iliac artery is elevated and dissected. Small blood vessels and lymphatic channels are carefully identified, secured with hemostatic clips, and divided. The incision is carried cephalad along the ventral surface of the aorta to the level of the origin of the IMA. Using a “split-and-roll” technique, the right para-aortic lymphatic tissue bundle is then mobilized from medial to lateral. The majority of the nodes are found in the aortocaval region and overlying the IVC. The lateral limit of the dissection is the fat plane on the lateral border of the IVC.

Special care is taken to identify and ligate the so-called “fellow’s vein,” a small perforating vein from the lymph nodes usually found inserting into the anterior surface of the vena cava just above the caval bifurcation. Failure to perform this step may result in inadvertent tearing of the vessel and significant bleeding. Similarly, control of the lumbar veins is essential to the safe removal of the lymphatic tissue residing lateral to and behind the IVC. The IVC may be gently rolled laterally and medially to identify these veins inserting into the posterolateral surface of the vessel. These are carefully isolated, doubly ligated with suture, and transected.

Left Aortic Lymph Node Dissection. The incision is continued along the ventral surface of the aorta. Using a “split-and-roll” technique, the lymphatic tissue is carefully elevated and mobilized from the ventral and lateral surface of the aorta. The lumbar arteries are identified, doubly ligated with suture, and divided. This step is essential to allow safe removal of all lymphatic tissue residing lateral to and behind the aorta. The posterior limit of the dissection is the anterior spinous ligament. Working from caudad to cephalad, the lymphatic tissue surrounding the aorta and vena cava is removed until the level of the renal veins is reached.

In the left lateral aortic area, the left ovarian artery is identified at its origin from the aorta, doubly ligated, and divided. With the lymph node specimen on gentle lateral traction, the lymphatic tissue immediately lateral to the aorta is then divided. Remaining lumbar vessels arising from the left posterolateral surface of the aorta are identified and carefully divided, working from the left common iliac artery to the level of the left renal vein. The left ovarian vein is identified, doubly ligated, and divided near its insertion into the left renal vein. Lymphatic tissue is carefully dissected from the undersurface of the left renal vein and renal artery. Meticulous use of hemostatic clips to secure the prominent lymphatics in this area is essential to reduce the risk of lymphorrhea and chylous ascites. The left aortic nodal specimen is then removed.

Interaortocaval Lymph Node Dissection. Attention is turned to the interaortocaval lymph nodes, residing between the great vessels. Working from caudad to cephalad, these are carefully resected from the level of the aortic bifurcation to the level of the left renal vein. Hemostatic clips are used to secure and divide the lymphatics as they course underneath the renal vein.

Right Common Iliac Lymph Node Dissection. Finally, attention is returned to the right side, and any remaining lymphatic tissue lateral to the right common iliac artery and IVC is carefully dissected and removed. The completed retroperitoneal lymph node dissection results in full exposure of the aorta, IVC, and left renal vessels (Figure 28-10).

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FIGURE 28-10. Completed open retroperitoneal lymph node dissection.

Laparoscopic Transperitoneal Aortic Lymph Node Dissection

The setup for the laparoscopic transperitoneal aortic lymph node dissection is similar to the laparoscopic pelvic lymph node dissection described earlier. The patient is placed in the dorsal lithotomy position with the legs secured in Allen stirrups. A Foley catheter is inserted, and an orogastric tube is placed by the anesthesiologist to provide gastric decompression. After initial trocar placement, the patient is placed in steep Trendelenburg position. Suggested equipment for the laparoscopic approach includes a 10-mm blunt port, two 5-mm trocars, a 5/10-mm trocar, 5- and 10-mm laparoscopic clip appliers, 5-mm graspers, and a 10-mm lymph node spoon. The procedure may be performed using a variety of available monopolar cautery devices for dissection and a vessel-sealing device. In a procedure that includes both pelvic and aortic dissection, the aortic lymph node dissection is performed first, before turning attention to the pelvis.

Trocar Placement

Using an open laparoscopy technique, the blunt 10-mm trocar is placed in the umbilicus, and the abdomen is insufflated. Under direct visualization, the 5-mm trocars are placed in the right and left lower quadrants, at a point approximately 1 cm superior to and 1 cm medial to the anterior superior iliac spine. Care should be taken to avoid injury to the inferior epigastric vessels. A 5/10-mm trocar is placed in the suprapubic area, carefully avoiding injury to the bladder. Individual trocar size and placement may vary depending on planned concurrent procedures, choice of instrumentation, the patient’s habitus, and prior surgical history.

Surgeon Positioning

The right-handed surgeon stands on the patient’s right side, holding in the right hand a dissecting monopolar cautery device placed through the 10-mm umbilical trocar and in the left hand a grasper placed through the right lower quadrant 5-mm trocar. The assistant stands on the patient’s left side. The assistant’s left hand holds the camera placed in the 5/10-mm suprapubic trocar, and the assistant’s right hand holds a grasper placed through the left lower quadrant 5-mm trocar.

Right Aortic Lymph Node Dissection

The laparoscopic aortic lymph node dissection begins with the right lateral aortic nodes, which overlie the IVC. Using the 2 graspers, the peritoneum overlying the right common iliac artery is elevated and incised with monopolar cautery. This incision is carried cephalad to the level of the duodenum and then carried caudad to the level of the sacrum.

Attention is turned first to the right lateral peritoneal leaflet created by this incision. Using a combination of blunt dissection and monopolar cautery, the surgeon develops the plane between the peritoneal leaflet and the lymph nodes overlying the IVC. The psoas muscle, ureter, IVC, and duodenum are identified.

The removal of lymphatic tissue begins at the lateral border of the right common iliac artery. The assistant may use the closed laparoscopic grasper to protect the ureter laterally. The surgeon uses a grasper to provide gentle traction on the nodal package. The monopolar cautery device may be used as both a blunt dissector and a cautery device to isolate small blood vessels and lymphatic channels, which are secured with hemostatic clips and divided. Larger vessels may be transected with a vessel-sealing device. The dissection is carried cephalad to the desired level, usually to the border of the duodenum near the insertion of the right ovarian vein into the IVC. The duodenum may be gently protected by the assistant, who grasps the peritoneal edge immediately caudal to the duodenum and retracts it superiorly. Hemostatic clips are particularly important at the superior border of the dissection. Particular care is taken to identify and ligate the so-called “fellow’s vein,” a small perforating vein from the lymph nodes usually found inserting into the anterior surface of the vena cava just above the caval bifurcation (Figure 28-11). The lymph node specimen is removed from the abdomen using the laparoscopic spoon.

images

FIGURE 28-11. Identification of the fellow’s vein. (Reproduced, with permission, from Sonoda Y, Barakat RR. Laparoscopic staging procedures. In: Levine DA, Barakat RR, Abu-Rustum NR, eds. Atlas of Procedures in Gynecologic Oncology. London, UK: Informa Healthcare; 2008:159, Figure 11.13a.)

Left Aortic Lymph Node Dissection

The superior extent of the peritoneal incision is extended in a transverse fashion along the duodenum toward the insertion of the left renal vein. This allows development of the left lateral peritoneal leaflet, exposing the left lateral aortic area. The IMA is identified at its origin from the ventral surface of the aorta approximately 2 cm above the aortic bifurcation. The left common iliac artery is identified. Using a grasper in the surgeon’s left hand, the IMA is elevated. Using the surgeon’s right hand instrument, blunt dissection is used to identify the left ureter and left psoas muscle in the window created by the elevated IMA. These 2 structures define the lateral limit of the dissection. Using a grasper, the assistant elevates the nodal package while the surgeon removes the nodes using a combination of blunt dissection, monopolar cautery, and hemostatic clips.

Interaortocaval Lymph Node Dissection

Attention is then turned to the interaortocaval nodes, which are resected in a similar manner. If the extent of dissection requires left para-aortic dissection cephalad to the IMA, the incision below the duodenum is extended further laterally along the left renal vessels. The dissection is carried cephalad to the IMA, working immediately lateral to the aorta, removing lymphatic tissue up to the level of the left renal vein. Hemostatic clips are particularly important to secure the prominent lymphatics at the superior border of the dissection, caudal to the renal vein. The specimen is removed.

Presacral Lymph Node Dissection

The presacral lymph nodes may be removed following completion of the left aortic dissection. The peritoneal incision is extended over the left common iliac vein, which is located immediately caudal to the aortic bifurcation. The lymphatic tissue in this area is carefully dissected, paying close attention to avoid injury to the vein.

The completed dissection exposes the aorta, vena cava, IMA, and common iliac vessels (Figure 28-12).

images

FIGURE 28-12. Completed laparoscopic aortic lymph node dissection.

Laparoscopic Extraperitoneal Aortic Lymph Node Dissection

The setup for the laparoscopic extraperitoneal aortic lymph node dissection is similar to the laparoscopic pelvic lymph node dissection described earlier. The patient is placed in the dorsal lithotomy position with the legs placed in Allen stirrups. A Foley catheter is inserted, and an orogastric tube is placed by the anesthesiologist to provide gastric decompression. After initial trocar placement, the patient is placed in steep Trendelenburg position. Suggested equipment for the laparoscopic approach includes a 10-mm blunt port, two 5-mm trocars, a 5/10-mm trocar, 5- and 10-mm laparoscopic clip appliers, 5-mm graspers, and a 10-mm lymph node spoon. The procedure may be performed using a variety of available monopolar cautery devices for dissection and a vessel-sealing device.

Diagnostic Laparoscopy

Prior to beginning the extraperitoneal procedure, a transperitoneal diagnostic laparoscopy is performed. One trocar is placed in the umbilicus, and one is placed in the right lower quadrant to allow insertion of a bowel grasper. The abdomen and pelvis are evaluated for evidence of peritoneal disease or bulky adenopathy. If necessary, a third trocar may be placed in the suprapubic area to assist with lysis of adhesions or retraction of the bowel.

Trocar Placement

A 15-mm incision is made in the left lower quadrant, 3 to 4 cm medial to the left anterior superior iliac spine. Two accessory trocars are eventually placed, one 10-mm trocar in the left midaxillary line and one 5-mm trocar in the anterior axillary line approximately 5 cm below the costal margin (Figure 28-13).

images

FIGURE 28-13. Laparoscopic extraperitoneal lymph node dissection: port placement guide. A. Trocar placement for diagnostic laparoscopy. B. Trocar placement for extraperitoneal aortic lymph node dissection.

Manual Dissection

The extraperitoneal space is developed using blunt dissection with a finger inserted through the 15-mm incision medial to the left anterior superior iliac spine. After traversing the abdominal fascia and muscle layer, the plane between the muscles and peritoneum is carefully developed bluntly without perforating the peritoneum. This step may be performed under direct laparoscopic visualization, using the camera inserted in the umbilical trocar. After identifying the psoas muscle and left common iliac artery, the peritoneum is further mobilized off of the anterior abdominal wall muscles, working in a cephalad direction.

Placement of Additional Trocars

After ensuring sufficient separation of the peritoneum from the muscle layer, the accessory trocars are carefully placed under direct manual guidance with the surgeon’s finger. Inadvertent puncture of the peritoneum at this point must be avoided, because it will make successful extraperitoneal insufflation impossible. Finally, the surgeon’s finger is removed and a balloon port is placed through the incision into the extraperitoneal space, under laparoscopic guidance. The extraperitoneal space is then insufflated with carbon dioxide gas in the usual fashion (Figure 28-14).

images

FIGURE 28-14. Laparoscopic extraperitoneal lymph node dissection: final port placement. (Reproduced, with permission, from Sonoda Y, Querleu D, Leblanc E. Extraperitoneal lymph node dissection. In: Levine DA, Barakat RR, Abu-Rustum NR, eds. Atlas of Procedures in Gynecologic Oncology. London, UK: Informa Healthcare; 2008:251, Figure 16.4.)

Identification of the Psoas Muscle

The psoas muscle is identified, and additional mobilization of the peritoneum off the psoas muscle may be accomplished under direct visualization using laparoscopic instruments. Using sharp and blunt dissection, the psoas muscle itself is then mobilized ventrally and laterally, releasing it from the underlying tissue, including the renal fascia. The mobilization creates space for the nodal dissection and creates a recessed area for dependent drainage of blood and irrigation fluid away from the dissection bed.

Identification of the Vasculature

The left common iliac artery is identified using blunt dissection. The left ureter and left ovarian vessels are left attached to the peritoneum, and they are therefore elevated off of the common iliac artery as the peritoneum is mobilized from the artery using blunt dissection. The artery is traced cephalad until the aortic bifurcation is identified. Working carefully in a cephalad direction, the IMA is identified, as well as the sympathetic trunk, which is most easily identified in this area coursing on the lateral surface of the aorta. Continuing cephalad, the dissection is carried to the level of the left renal vein.

Left Aortic Dissection

The left common iliac nodes and left lateral aortic nodes are carefully dissected using laparoscopic graspers, a monopolar or bipolar cautery instrument, and a vessel-sealing device. Hemostatic clips are applied as needed, particularly in the area of prominent lymphatics immediately caudal to the left renal vein. The lymphatic tissue is removed from the lateral aspect of the aorta, remaining ventral to the sympathetic trunk. Care is taken to avoid injury to the lumbar veins and the azygos vein. The left ovarian artery must also be carefully identified at its origin from the aorta 2 to 3 cm below the renal vessels.

Right Aortic Dissection

The right aortic dissection begins with identification of the right ureter, which is protected laterally using a closed grasper. The right ovarian artery is identified and divided (if desired) at its origin from the aorta 2 to 3 cm caudal to the right renal vessels. The right common iliac and right aortic nodes are carefully dissected free, avoiding injury to the vena cava and right ureter. Small perforators from the vena cava to the nodal package (eg, the so-called “fellow’s vein”) must be carefully identified and divided. Avulsion of these vessels may cause hemorrhage. The interaortocaval and presacral nodes may then be dissected, with care taken to avoid injury to the left common iliac vein and middle sacral vein.

Completion of Dissection

The limits of the laparoscopic extraperitoneal dissection are the left renal vein cephalad and the common iliac arteries caudad (Figure 28-15). If radiation therapy is planned, the lower limit of the dissection is marked with clips to assist the radiation oncologist with treatment planning. At the conclusion of the procedure, it is essential to fenestrate the peritoneum along the left paracolic gutter, allowing postoperative lymphatic fluid to drain into the peritoneal cavity, thus reducing postoperative symptomatic lymphocele formation.

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FIGURE 28-15. Completed laparoscopic extraperitoneal aortic lymph node dissection. 1 = Right common iliac artery; 2 = Aorta; 3= Left common illiac artery. (Reproduced, with permission, from Sonoda Y, Querleu D, Leblanc E. Extraperitoneal lymph node dissection. In: Levine DA, Barakat RR, Abu-Rustum NR, eds. Atlas of Procedures in Gynecologic Oncology. London, UK: Informa Healthcare; 2008:255, Figure 16.15b.)

INGUINOFEMORAL LYMPH NODE DISSECTION

Procedure Overview


Box 28-5 Master Surgeon’s Corner

images From lateral to medial, the contents of the femoral triangle include the femoral nerve, femoral artery, femoral vein, empty space, and lymph nodes (N-A-V-E-L).

images Palpation of the femoral triangle is essential to the proper identification of the femoral artery and adjacent landmarks.

images In sentinel lymph node dissection, any residual radioactivity in the dissection bed after sentinel node removal must be pursued with further dissection, because more than 1 sentinel node may be present.


Indications and Historical Perspective

Inguinofemoral lymph node dissection is most commonly indicated in the staging and treatment of vulvar malignancy. Occasionally, it may be performed for surgical resection of clinically apparent nodal involvement by other gynecologic malignancies. The use of sentinel lymph node mapping in primary vulvar malignancy has been evaluated in 2 prospective trials and may be appropriate in selected cases.3

Preoperative Preparation

Considerations for preoperative preparation are similar to those listed earlier for pelvic and aortic lymph node dissections, except that bowel preparation is not necessary. The consent discussion with the patient should include special emphasis on the elevated risk of lower extremity lymphedema after inguinofemoral dissection. Pre- or postoperative instruction regarding lymphedema prevention and management is recommended.

The procedure is usually performed in conjunction with vulvar resection requiring the dorsal lithotomy position. The legs are secured in Allen stirrups, and the bilateral groins are prepped and draped using sterile technique. The legs are positioned with the knees bent and the thigh only slightly flexed at the hip, providing adequate exposure of the entire groin area. The inguinofemoral lymph node dissection is generally performed first, with skin closure performed prior to potential contamination of the field by the vulvar portion of the procedure. Required instrumentation includes skin retractors and an electrocautery device. If sentinel lymph node mapping is planned, preoperative injection with radioisotope is performed, and blue dye is injected in the operating room as described later in this section.

Operative Procedure


Box 28-6 Caution Points

images Care is taken to keep the subcutaneous fat attached to the skin, because making the flaps too thin may lead to skin necrosis.

images Meticulous isolation and clipping of lymphatic channels will reduce postoperative lymphocele formation.

images Control of the saphenous vein and its tributaries is essential to reduce troublesome bleeding during the medial portion of the dissection.


Inguinofemoral Lymph Node Dissection

Creation of Flaps

The procedure begins with palpation of the groins to identify any clinically apparent adenopathy. If sentinel lymph node injection has been performed, the gamma probe is used to localize the sentinel lymph nodes. These assessments may guide the location of the skin incision, which is generally 8 to 10 cm long and parallel to the inguinal ligament. The skin edges are elevated with skin hooks, and a plane is created between the subcutaneous adipose tissue and the underlying lymphatic tissue. This may be accomplished with sharp dissection using a scalpel or electrocautery. Care is taken to keep the subcutaneous fat attached to the skin, because making the flaps too thin may lead to skin necrosis.

Identification of Landmarks

The limits of the dissection are identified. The medial boundary of dissection is the lateral border of the adductor longus muscle. This muscle is palpated, and the incision is carried down to the level of its fascia. The lateral boundary of dissection is the medial border of the sartorius muscle, which is easily identified. The cephalad boundary is the mons pubis and pubic tubercle medially, and the aponeurosis of the external oblique muscle laterally.

Superficial Lymph Node Dissection

The dissection begins at the cephalad boundary, near the inguinal ligament. The fat pad containing the superficial lymph nodes is elevated from the aponeurosis of the external oblique muscle. Working from cephalad to caudad, the fat pad is mobilized inferiorly to the edge of the inguinal ligament. The dissection is accomplished using sharp and blunt dissection, with electrocautery and hemostatic clips applied as needed. Medially, the external inguinal ring and superficial external pudendal vessels are identified. Laterally, the superficial circumflex iliac vessels are identified. From lateral to medial, the contents of the femoral triangle include the femoral nerve, femoral artery, femoral vein, and lymph nodes.

Deep Lymph Node Dissection: Femoral Artery

The femoral nerve is identified laterally, emerging caudad to the inguinal ligament. Working toward the femoral triangle, the superficial dissection is carried deeper by incision of the cribriform fascia overlying the common femoral artery. The artery may be identified by palpation. This incision is carried along the ventral aspect of the artery. The superficial external pudendal artery may be encountered at its origin from the femoral artery at the most medial and cephalad area of the dissection. This vessel should be ligated and divided. Other branches of the femoral artery may be encountered, including the superficial epigastric artery and the superficial circumflex iliac artery.

Deep Lymph Node Dissection: Femoral Vein

The nodal package is elevated and the dissection is continued from lateral to medial, freeing the lymphatic tissue from the ventral surface of the femoral vein. The greater saphenous vein drains into the common femoral vein near the cephalad limit of the dissection, at the point where the superficial external pudendal artery crosses the common femoral vein. The greater saphenous vein is skeletonized approximately 1 to 2 cm from its insertion. It is doubly ligated with permanent suture and divided at its insertion into the common femoral vain. Care is taken not to compromise the lumen of the common femoral vein as this suture is placed. Small tributaries of the saphenous vein are carefully identified and ligated as they are encountered during the medial portion of the deep lymph node dissection. Any remaining attachments of the specimen to the dissection bed are carefully divided, and the specimen is removed. The completed dissection exposes the structures of the femoral triangle (Figure 28-16).

images

FIGURE 28-16. Femoral triangle. 1 = adductor longus muscle; 2 = left femoral vein; 3= left femoral artery; 4 = Sartorius muscle. (Reproduced, with permission, from Gemignani ML. Surgery for carcinoma of the vulva. In: Levine DA, Barakat RR, Abu-Rustum NR, eds. Atlas of Procedures in Gynecologic Oncology. London, UK: Informa Healthcare; 2008:52, Figure 3.24.)

Completion of the Dissection

The dissection bed is irrigated and inspected for hemostasis. Hemostatic clips are placed on small vessels and lymphatics as needed. If desired, the sartorius muscle may be transposed over the vessels at this point in the procedure. The muscle is transected with electrocautery at its tendinous attachment to the anterior superior iliac spine, and it is transposed medially over the vessels. The proximal portion of the muscle is then sutured to the inguinal ligament and pectineal fascia using interrupted delayed-absorbable sutures. The subcutaneous tissue is reapproximated with interrupted delayed-absorbable sutures, and the skin incision is closed with staples.

Inguinofemoral Sentinel Lymph Node Mapping

Sentinel lymph node mapping in vulvar malignancy uses a combined approach with both radioisotope and blue dye used to localize the sentinel lymph nodes.

Radioisotope Injection

The radioisotope injection may be given the morning of surgery or the day prior. Filtered technetium 99m sulfur colloid is used, with 0.1 to 0.5 mCi of the colloid injected at the edge of the vulvar lesion. A preoperative lymphoscintigram is performed approximately 2 to 6 hours after the injection. This study may identify both the laterality and number of sentinel lymph nodes, thus assisting in preoperative planning. In the operating room, after positioning the patient, the gamma probe is used to localize the sentinel node in the groin, and radioactivity counts are measured at this site as well as at the primary injection site. The groin site of maximal radioactivity is marked.

Blue Dye Injection

The injection of blue dye is performed in the operating room after the induction of anesthesia. Approximately 4 mL of isosulfan blue dye (described earlier) is injected circumferentially around the lesion in an intradermal fashion, at the junction of tumor and the normal surrounding skin. Deeper cutaneous injection may be added in the case of a large lesion. Injection directly into the lesion is not effective.

Intraoperative Localization

After prepping and draping the patient, the sterile-draped gamma probe is used to confirm the location of the sentinel node at the previously marked groin site.

Skin Incision

A small incision is made directly over the area of maximal radioactivity, parallel to the inguinal ligament. If a full inguinofemoral lymphadenectomy is planned, this incision may be extended later.

Dissection of the Sentinel Node

The fatty tissue surrounding the lymph nodes is carefully dissected, identifying the blue lymphatic channels leading to the sentinel lymph node. The gamma probe is used to guide the dissection until the blue-stained sentinel node is found (Figure 28-17). The node is carefully dissected free from the surrounding tissue and removed. Any node that exhibits radioactivity, regardless of color, is also removed. The gamma probe is used to obtain ex vivo counts of all nodes removed, and the color and radioactivity status of each resected node are recorded.

images

FIGURE 28-17. Inguinofemoral sentinel lymph node mapping.

Postexcision Radioactivity Counts

The lymphatic basin is checked for radioactivity after the sentinel node is removed, and any area of residual radioactivity is pursued with dissection. Residual lymphatic basin counts should be reduced 4- to 10-fold over the initial counts in the groin.

Completion of the Dissection

The skin incision may be closed with absorbable sutures. Alternatively, if an inguinofemoral lymphadenectomy is planned, the incision is extended at this point, and the dissection is performed as described earlier.

POSTOPERATIVE CARE

Standard postoperative care is required after lymph-adenectomy. Although the historical literature reports the use of intraperitoneal drains after lymph node dissection, recent data do not support their routine placement in the absence of other factors, such as unusual concern for delayed bleeding, infection, or lymphor-rhea, or concurrent procedures requiring drain placement. In contrast, drains are routinely placed in the groin after inguinofemoral lymph node dissection and left in place until lymphatic fluid output becomes minimal. This practice reduces the occurrence of inguinal lymphocele, which can lead to pain, infection, and wound breakdown.


Box 28-7 Complications and Morbidity

images Hemorrhage: Excessive bleeding is a potential issue during any lymph node dissection and is best avoided by meticulous dissection, identification of vascular structures, and use of hemostatic clips where indicated.

images Nerve injury: Several nerves lie in close proximity to the vascular supply and lymphatic drainage of the gynecologic organs. Knowledge of the anatomic location of these structures is essential, and they must be carefully identified and protected. Symptoms of nerve injury may vary in duration and severity. In general, injury of the genitofemoral nerve causes numbness and paresthesia of the medial thigh without motor deficit. Injury of the obturator nerve causes weakness in abduction of the thigh.

images Lymphocele: Postoperative lymphocele formation is very common and is frequently an asymptomatic finding on postoperative imaging of the abdomen and pelvis. In some instances, however, the fluid collections may cause persistent pain or fever, necessitating drainage. This can usually be accomplished by interventional radiology.

images Chylous ascites: Persistent large-volume lymphorrhea may cause clinically significant ascites. This occurs most commonly following extensive aortic lymph node dissection and, in some cases, may require drainage by paracentesis. The risk of chylous ascites is reduced by meticulous identification and clipping of lymphatic vessels.

images Venous thromboembolism: Patients undergoing lymph node dissection for malignancy are at elevated baseline risk for deep vein thrombosis. This risk is further increased by excessive manipulation of the venous vasculature during the dissection, which may cause trauma to the vessel wall. Therefore, care should be taken to retract veins gently and for short periods of time to reduce the risk of injury.

images Lymphedema: The incidence of lymphedema following lymph node dissection varies by procedure. Several factors contribute to an elevated risk, including obesity, pre-existing venous stasis or lymphedema, prior limb surgery, and radiation treatment.


REFERENCES

1. Cibula D, Abu-Rustum NR. Pelvic lymphadenectomy in cervical cancer: surgical anatomy and proposal for a new classification system. Gynecol Oncol. 2010;116:33-37.

2. Abu-Rustum NR, Khoury-Collado F, Gemignani ML. Techniques of sentinel lymph node identification for early-stage cervical and uterine cancer. Gynecol Oncol. 2008;111(suppl):S44-S50.

3. Levenback C. Update on sentinel lymph node biopsy in gynecologic cancers. Gynecol Oncol. 2008;111(suppl):S42-S43.



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