Partial Nephrectomy Is Not Associated With an Overall Survival Advantage Over Radical Nephrectomy in Elderly Patients With Stage Ib-II Renal Masses: An Analysis of the National Cancer Data Base

BACKGROUND: Partial nephrectomy (PN) is recommended for localized T1a (<= 4cm) renal masses and is preferred over radical nephrectomy (RN) for amenable T1b/T2 (>4 cm) tumors. The objective of the current study was to assess overall survival (OS) differences between PN and RN in patients with T1 and T2 renal cell carcinoma (RCC). METHODS: The National Cancer Data Base was queried for patients with T1 and T2 RCC who underwent PN or RN from 2004 to 2014. Trends in surgery were evaluated using Cochran-Armitage tests. Differences in OS were assessed using adjusted Kaplan-Meier methods. The effects of procedure on OS were analyzed using propensity score-based, weighted Cox proportional hazards models. RESULTS: In total, 212,016 patients with T1 and T2 RCC who underwent either RN (59.7%) or PN (40.3%) were included. The use of PN rose from 2004 to 2014 (T1a: from 40.6% to 71.4%; T1b/T2: from 8.4% to 26.5%; P<.01). Adjusted 5-year OS was longer for patients who underwent PN in both subsets, although effect magnitude was reduced in the T1b/T2 cohort (T1a: 89.6% vs 85.1%; hazard ratio [HR], 0.73; 95% confidence interval [CI] 0.70-0.75; P<.01; T1b/T2: 82.5% vs 80.8%; HR, 0.88; 95% CI, 0.83-0.94; P =.01). The benefit of PN on OS diminished as age and time from diagnosis increased: no OS improvement was observed in patients age >= 75 years who had T1b/T2 tumors (HR, 0.89; 95% CI, 0.76-1.06). CONCLUSIONS: Receipt of PN is associated with improved OS in patients with T1a RCC. No procedure-related differences in OS were observed for patients age >= 75 years who had tumors measuring >4cm. Decisions to undergo PN for T1b/T2 tumors should be based on individualized risk assessment. (C) 2018 American Cancer Society.