Anatomical Refinement of Pelvic Lymphadenectomy in Extraperitoneal Radical Prostatectomy Based on a Constant Venous Landmark.

Background/Objectives: Extended pelvic lymph node dissection (ePLND) is the standard approach for staging intermediate- and high-risk prostate cancer (PCa), but the optimal extent of the procedure is still being debated due to the need to balance staging benefits with postoperative complications. This study aimed to assess whether the deep circumflex iliac vein, a consistent anatomical venous landmark, can guide a more selective dissection template that maintains staging accuracy while reducing morbidity. Methods: We conducted a retrospective analysis of 32 patients with intermediate- or high-risk PCa and histologically confirmed nodal metastases who underwent minimally invasive extraperitoneal radical prostatectomy with ePLND between 2018 and 2024. The lymph nodes located above (supra-venous) and below (infra-venous) the landmark vein were dissected separately and analysed histologically. Postoperative lymphoceles and related complications were recorded. Results: No metastatic lymph nodes were found in the subvenous region across all patients. All positive nodes were located cranially to the landmark, primarily in the obturator, internal iliac and proximal external iliac regions. Lymphoceles occurred in all patients, 62.5% of whom were symptomatic, 43.8% of whom had a fever, and 18.8% of whom were septic and required drainage. Four patients underwent laparoscopic reintervention for recurrent lymphoceles. Conclusions: The absence of metastatic involvement in the subvenous region suggests it is an oncologically low-yield zone. A refined dissection template omitting this area, guided by a reproducible venous landmark, may lower complication rates without compromising staging accuracy. Prospective validation is warranted before clinical adoption.