Laparoscopic and Robotic-Assisted Laparoscopic Pelvic Lymph Node Dissection

Since its initial description in 1991, laparoscopic pelvic lymph node dissection (LPLND) has evolved from both a technical and a medical standpoint. The introduction of robotic-assisted technology has allowed the urologic surgeon to take advantage of the superior vision and control of the robotic system when performing robotic-assisted laparoscopic pelvic lymph node dissection (r-LPLND) for prostate cancer and bladder cancer staging. Pelvic lymph node dissection (PLND), in general, has been the subject of a great deal of debate regarding the extent of the dissection templates in high-risk prostate cancer, as well as the role for PLND in low-risk disease. Several predictive nomograms have noted that patients with prostate-specific antigen (PSA) levels below 10 ng/mL and Gleason scores below 7 are at a very low risk for lymph node involvement. Consequently, surgeons have questioned the need for PLND in this patient cohort. Other surgeons advocate for wider, more aggressive dissections than the standard dissection template in patients with higher risk disease. Conversely, there is greater consensus in the bladder cancer literature regarding the need for a wider dissection template to achieve an adequate therapeutic and diagnostic outcome after PLND.

Indications and Contraindications

LPLND is rarely indicated as an independent procedure separate from radical cystectomy or prostatectomy. The patients who may benefit from an independent LPLND include those who are at a high risk for having metastatic prostate cancer and are deciding among local therapies alone (radiation, perineal prostatectomy, or cryotherapy), systemic therapy (hormonal therapy), and multimodal therapy. Unfortunately, cross-sectional imaging studies such as computed tomography (CT) and magnetic resonance imaging (MRI) have very low sensitivities for detecting lymph node involvement, and therefore PLND remains the gold standard for lymph node staging. Therefore, patients with high-risk features, including a Gleason score of 8 or higher, suggestion of extracapsular extension on digital rectal examination or MRI, PSA level above 20 ng/mL, a positive seminal vesicle biopsy, or stage T2b or higher disease, may benefit from a staging PLND before committing to radical prostatectomy with its associated morbidity.

r-LPLND is primarily performed in conjunction with robotic-assisted laparoscopic prostatectomy based on the presence of preoperative risk factors of lymph node involvement. LPLND is also indicated in salvage procedures after failed radiation therapy, in patients undergoing robotic-assisted laparoscopic radical cystectomy, and rarely in patients with metastatic urethral and penile cancer.

Absolute contraindications to LPLND include bleeding diathesis, active infection, severe respiratory disease (chronic obstructive pulmonary disease [COPD]), and severe coronary artery disease. Relative contraindications to LPLND are often related to surgeon experience. These may include extensive prior surgery in the lower abdomen and pelvis (inguinal hernia repair with mesh), morbid obesity, iliac artery tortuosity or aneurysm, history of inflammatory bowel disorders (extensive diverticulitis, perforated appendicitis, and inflammatory bowel disease), and prior pelvic radiation.

Patient Preoperative Evaluation and Preparation

Before LPLND, routine laboratory tests should be performed, including a complete blood count, serum chemistry panel, coagulation studies, PSA testing, urinalysis, and urine culture. It is also critically important to determine whether the patient has any evidence of metastatic disease. Depending on the clinical indication, chest radiography, CT or MRI of the abdomen and pelvis, nuclear bone scan, and ProstaScint scan (Aytu BioScience, Inc., Englewood, Colo.) can be used to evaluate for the presence of metastatic disease. The patient is instructed to discontinue nonsteroidal anti-inflammatory medications, aspirin, and any other anticoagulants with sufficient time before surgery to allow for return to normal coagulation. All appropriate medical and cardiopulmonary clearances should be obtained. The patient is instructed not to eat or drink after midnight on the night before surgery. Preoperative bowel preparation is optional but may be more important in patients who have a history of prior abdominal surgery or inflammatory bowel disorders. The patient receives a perioperative dose of a first-generation cephalosporin antibiotic. Additional antibiotics with gram-negative and anaerobic coverage should be considered if prostatectomy or cystectomy is to be performed.

Operating Room Configuration and Patient Positioning

Room configuration and patient positioning are, for the most part, similar for LPLND whether it is done as an independent procedure or as part of a radical prostatectomy or cystectomy. There are slight room configuration differences depending on whether a laparoscopic or a robotic approach is being used.

When an LPLND is performed, the patient is placed in either the supine position or in a low dorsal lithotomy position with a full-length gel pad mattress placed underneath. If the dorsal lithotomy position is chosen, careful attention is paid to minimize pressure along the lateral aspect of the knee where the common peroneal nerve lies. An r-LPLND is performed exclusively in the dorsal lithotomy position. Sequential compression devices are applied to the patient’s legs to minimize the risk of deep venous thrombosis (DVT). The arms are carefully tucked and padded along the patient’s side in the neutral anatomic position with the thumbs pointing toward the ceiling. Attention is paid to ensure that the arms and hands are under no traction or pressure. A Foley catheter is placed once the patient has been prepared and draped when a PLND is performed in conjunction with radical prostatectomy or cystectomy. If only a PLND is being performed, then a urinary catheter is placed before preparation and draping.

For LPLND, the room is configured with the monitor at the foot of the bed, between the patient’s legs ( Fig. 13-1, A ). The surgeon stands on the left side of the patient, and the surgical assistant stands on the patient’s right side. For r-LPLND, the robotic patient-side cart is docked between the patient’s legs, the operating surgeon sits at the robotic console, and the assistant surgeon stands on the side of the patient where there is only one robotic arm being used ( Fig. 13-1, B ).

Operating Room Configuration and Patient Positioning

Room configuration and patient positioning are, for the most part, similar for LPLND whether it is done as an independent procedure or as part of a radical prostatectomy or cystectomy. There are slight room configuration differences depending on whether a laparoscopic or a robotic approach is being used.

When an LPLND is performed, the patient is placed in either the supine position or in a low dorsal lithotomy position with a full-length gel pad mattress placed underneath. If the dorsal lithotomy position is chosen, careful attention is paid to minimize pressure along the lateral aspect of the knee where the common peroneal nerve lies. An r-LPLND is performed exclusively in the dorsal lithotomy position. Sequential compression devices are applied to the patient’s legs to minimize the risk of deep venous thrombosis (DVT). The arms are carefully tucked and padded along the patient’s side in the neutral anatomic position with the thumbs pointing toward the ceiling. Attention is paid to ensure that the arms and hands are under no traction or pressure. A Foley catheter is placed once the patient has been prepared and draped when a PLND is performed in conjunction with radical prostatectomy or cystectomy. If only a PLND is being performed, then a urinary catheter is placed before preparation and draping.

For LPLND, the room is configured with the monitor at the foot of the bed, between the patient’s legs ( Fig. 13-1, A ). The surgeon stands on the left side of the patient, and the surgical assistant stands on the patient’s right side. For r-LPLND, the robotic patient-side cart is docked between the patient’s legs, the operating surgeon sits at the robotic console, and the assistant surgeon stands on the side of the patient where there is only one robotic arm being used ( Fig. 13-1, B ).

Trocar Placement

After the patient is prepared and draped in the standard sterile fashion, attention is turned toward peritoneal access. A 12-mm skin incision is made superior to the umbilicus. Using either a Veress needle or the Hasson technique, access into the peritoneal cavity is obtained. Pneumoperitoneum is established with CO ₂gas to a pressure of 15 mm Hg. A 10/12-mm camera port is then placed through the supraumbilical incision. If an r-LPLND is being performed, the 30-degree robotic laparoscope in the down position is inserted through the umbilical trocar. Alternatively, if an LPLND is being performed, the 10-mm, 30-degree laparoscope is used. A brief survey of the pelvis is then performed to evaluate for any trocar placement injuries and for the presence of any adhesions that may interfere with further port placement and to identify the location of the iliac vessels as surgical landmarks.

The remaining port locations are based on whether an r-LPLND or LPLND is being performed. When a robotic-assisted technique is used, our preference is to place an 8-mm robotic trocar approximately 7 to 8 cm (roughly one handbreadth) lateral to the level of the umbilicus on the right side. An additional 8-mm robotic trocar is placed one handbreadth further lateral on the right side, again at the level of the umbilicus. On the left side, a 10/12-mm assistant trocar is placed just superior to the level of the umbilicus approximately 6 to 7 cm from the midline. Finally, the third robotic, 8-mm trocar is placed on the left side approximately 10 to 11 cm (one and a half handbreadths) lateral to the umbilicus. Alternatively, port placement for r-LPLND can be the mirror image of the aforementioned configuration if the surgeon’s preference is to have two robotic arms on the patient’s left side ( Fig. 13-2, A ).