Determinants of long-term survival of patients with locally advanced prostate cancer: the role of extensive pelvic lymph node dissection

BACKGROUND: The therapeutic effect of pelvic lymph node dissection (PLND) during radical prostatectomy (RP) due to prostate cancer (PCa) is still under debate. We aimed at assessing the impact of more extensive PLND on cancer-specific mortality (CSM) in patients treated with surgery for locally advanced PCa. METHODS: We examined data of 1586 pT3-T4 PCa patients treated with RP and extended PLND between 1987 and 2012 at a tertiary referral care center. Univariable and multivariable Cox regression analyses tested the relationship between the number of nodes removed and CSM rate, after adjusting for potential confounders. Survival estimates were based on the multivariable models. RESULTS: The average number of nodes removed was 19 (median: 17; interquartile range: 11-23). Mean and median follow-up were 80 and 72 months, respectively. At multivariable analyses, Gleason score 8-10 (hazard ratio (HR): 2.5) and a higher number of positive nodes (HR: 1.06) were independently associated with higher CSM rate (all P < 0.05). Conversely, higher number of removed LNs (HR: 0.94) and adjuvant radiotherapy (HR: 0.54) were independent predictors of lower CSM rates (all P <= 0.03). CONCLUSIONS: In pT3-T4 PCa patients, removal of a higher number of LNs during RP was associated with higher cancer-specific survival rates. This supports the role of more extensive PLNDs in this patient group. Further prospective studies are needed to validate our findings.