Novel Use of Fluorescence Lymphangiography During Robotic Groin Dissection for Penile Cancer

To describe a novel technique of robotic inguinal lymphadenectomy with near infrared fluorescence imaging (NIRF) using indocyanine green (ICG) to facilitate lymph node identification during robotic groin dissection for penile cancer.

The patient is placed in lithotomy position with access to the groin. Three robotic ports and 1 assist port are placed in a V configuration below the tip of femoral triangle. Intradermal ICG is injected at the base of the penis (0.5 mL of 2 mg/kg concentration in normal saline), and the lymphatic channels and nodes are visualized using NIRF in the robotic console approximately 15 minutes after injection. The surgical template established in the open approach is then replicated using NIRF to ensure complete resection of the affected nodes.

A total of 10 groin dissections in 5 patients have been completed using this technique, with an average lymph node yield of 7 per groin (range 5-13 lymph nodes). Mean operative time per groin was 207 minutes (range 164-258 minutes) and estimated blood loss was 38 mL (range 25-50 mL). Mean length of hospital stay was 1.8 days (range 0-4 days). Identification of the lymphatic drainage pattern from the superficial to deep groin nodes to pelvic nodes underneath the inguinal ligament was identified in all patients. With a mean follow-up of 10 months (range 3-16 months), there have been no postoperative infections, lymphatic leaks, wound breakdown, or necrosis. Pathologically involved lymph nodes were identified using NIRF.

Our novel technique of robotic inguinal lymphadenectomy with fluorescence lymphangiography allows for identification and excision of both superficial and deep groin nodes with a significant reduction in morbidity compared with the open approach. Prospective studies are required to ensure long-term efficacy and results of this procedure.