The impact of the extent of lymph-node dissection on biochemical relapse after radical prostatectomy in node-negative patients

Abstract

Background: The therapeutic role of pelvic lymph-node dissection (PLND) for prostate cancer (PCa) is still unclear. The aim of this study was to assess the impact of the number of lymph nodes (LN) retrieved at PLND during radical prostatectomy (RP) on biochemical relapse (BCR) in node-negative patients.

Patients and methods: From October 1995 to June 2009, 1510 consecutive PCa patients underwent RP at the University of Bologna hospital. A retrospective analysis was performed on 614 pT2-4N0 patients with a minimum follow-up of 12 months. All 614 patients underwent limited or extended PLND during RP. BCR-free survival was estimated using the Kaplan-Meier method. Cox regression was applied to analyse survivals rates. Patients were divided into two groups: group 1 (n=295) had 1 to 9 retrieved LNs and group 2 (n=319) had 10 or more retrieved. The parameters analysed were age, PSA, clinical and pathological Gleason score (GS), stage, margin status and adjuvant radiotherapy (ART). BCR was defined as PSA greater than 0.2 ng/ml.

Results: Mean follow-up time was 62.5+/-39.7 months. Group 2 showed a significantly lower BCR than group 1 (p=0.019). LN group, PSA, clinical and pathological GS, pathological stage and ART all showed an independent and significant relationship with BCR using multivariate analysis.

Conclusion: In node-negative patients, a more extensive PLND affects BCR-free survival positively. A more extensive PLND may have a therapeutic role by removal of micrometastases.