Survival Patterns among Patients with N1 and M1a Prostate Cancer Treated with Radical Prostatectomy and Lymphadenectomy

Purpose: The role of radical prostatectomy (RP) and lymph node dissection (LND) in men with prostate cancer (PCa) and clinical nodal disease (cN1 and cM1a) remains a matter of debate. This study aims to compare biochemical recurrence-free survival (BRFS), distant metastasis free survival (DMFS), cancer specific survival (CSS), and overall survival (OS) between patients with cN1 or cM1a PCa treated at a single institution. Patients and methods: We identified 207 men with PCa and at least one pelvic and/or retroperitoneal node involved, who underwent RP and LND between October 2007 and September 2022. Patients were classified as either cN1 (pelvic nodal disease, n=150) or cM1a (retroperitoneal nodal disease, n=57). Kaplan-Meyer curves and Cox regression models were used to compare survival outcomes. Results: Baseline and main pathological features were well balanced between the two groups. Patients in the cM1a cohort had a higher number of clinically positive nodes (p<0.01), with a larger median long axis diameter. A similar proportion of salvage treatments were given to both cohorts. Median follow-up was 67 months. On multivariable Cox regression analysis, cN1 vs cM1a was not a statistically significant predictor of BRFS (HR 0.83 95% CI, 0.53, 1.3, p=0.42), DMFS (HR 1.0, 95%CI 0.58, 1.5, p=0.82), CSS (HR 1.05, 95%CI 0.45, 2.4, p=0.91), OS (HR 0.87, 95%CI 0.46, 1.7, p=0.84). Conclusion: These results obtained over a median follow-up of more than 5 years show that patients undergoing RP and LND have similar oncologic outcomes regardless of the location of lymphadenopathy (pelvic vs retroperitoneal).