Small-volume lymph node involvement and biochemical recurrence after robot-assisted radical prostatectomy with extended lymph node dissection in prostate cancer

Background We investigated prognostic factors for biochemical recurrence (BCR) after robot-assisted radical prostatectomy (RARP) with extended pelvic lymph node (LN) dissection. Methods We included 173 patients who underwent RARP with extended pelvic LN dissection without neoadjuvant therapy at our hospital between October 2010 and April 2018. BCR was defined as prostate serum antigen (PSA) levels ≥ 0.2 ng/mL; BCR-free survival rates were determined using Kaplan–Meier analysis. We used Cox regression analysis to evaluate effects of PSA and pathologic variables on BCR. Results Median follow-up was 27.9 (range 6.1–86.9) months. Five-year BCR-free survival was 89.5%. In multivariate analysis, positive LNs (HR 7.117; 95% CI 2.826–17.925; P