Identifying low cancer‐specific mortality risk lymph node‐positive radical prostatectomy patients

Objectives To identify low cancer‐specific mortality (CSM) risk lymph node‐positive (pN1) radical prostatectomy (RP) patients. Methods Within Surveillance, Epidemiology and End Results database (2010–2015) pN1 RP patients were identified. Kaplan–Meier plots and multivariable Cox‐regression (MCR) models were used. Pathological characteristics were used to identify patients at lowest CSM risk. Results Overall, 2197 pN1 RP patients were identified. Overall, 5‐year cancer‐specific survival (CSS) rate was 93.3%. In MCR models ISUP GG1‐2 (hazard ratio [HR]: 0.12, p < 0.001), GG3 (HR: 0.14, p < 0.001), GG4 (HR: 0.35, p = 0.002), pT2 (HR: 0.27, p = 0.012), pT3a (HR: 0.28, p = 0.003), pT3b (HR: 0.39, p = 0.009), and 1–2 positive lymph nodes (HR: 0.64, p = 0.04) independently predicted lower CSM. Pathological characteristics subgroups with the most protective hazard ratios were used to identify low‐risk (ISUP GG1‐3 and pT2–3a and 1–2 positive lymph nodes) patients versus others (ISUP GG4‐5 or pT3b–4 or ≥3 positive lymph nodes). In Kaplan–Meier analyses, 5‐year CSS rates were 99.3% for low‐risk ( n = 480, 21.8%) versus 91.8% ( p < 0.001) for others ( n = 1717, 78.2%). Conclusions Lymph node‐positive RP patients exhibit variable CSS rates. Within this heterogeneous group, those at very low risk of CSM may be identified based on pathological characteristics, namely ISUP GG1‐3, pT2–3a, and 1–2 positive lymph nodes. Such stratification scheme might be of value for individual patients counseling, as well as in design of clinical trials.