Pre-prostatic tissue removed in robotic assisted lymph node dissection for prostate cancer contains lymph nodes

Objective: The on-going discussion about extent and best template for pelvic lymph dissection (PLND) motivated us to analyse pre-prostatic tissue (PPT) for lymph nodes and metastases. Materials and Methods: From December 2010 to August 2011 PPT was sent for histopathological evaluation during 80 robotic assisted radical prostatectomies (RARP) and one extended staging lymph node dissection. All patients had either a limited (lPLND, n = 44) or an extended lymph node dissection (ePLND, n = 36). Clinical data were retrospectively analyzed and compared to histopathological findings. Results: Lymph nodes were found in PPT in 10/80 (12.5%) patients after RARP and in the one patient after staging ePLND. Mean number of lymph nodes detected in PPT of them was 1.2 (range 1-3). Clinically no differences were found between patients with or without lymph nodes in PPT. In the standard template of either ePLND or lPLND the average number of lymph nodes was 13 (range 2-56). Herein metastases were found in 10 ( 12.5%) patients after RARP and in the patient after staging ePLND. A metastasis in PPT was only found after staging ePLND. Conclusions: Pre-prostatic tissue might contain lymph nodes that potentially harbour metastases. In the intention to perform the most accurate staging this tissue should be considered for histopathological evaluation.