Nephron-sparing Surgery Is Equally Effective to Radical Nephrectomy for T1BN0M0 Renal Cell Carcinoma: A Population-based Assessment

Objectives: To test the effect of nephron-sparing surgery (NSS) vs radical nephrectomy (RN) on cancer-specific mortality (CSM) in patients with T1bN0M0 renal cell carcinoma (RCC) in a population-based cohort. To date, only few series from tertiary care centers supported the use of NSS for T1bN0M0 (range 4-7 cm) RCC. Methods: The Surveillance, Epidemiology, and End Results database allowed us to identify 275 NSS (5.3%) and 4866 RN (94.7%) patients treated for T1bN0M0 RCC between 1988 and 2004. Analyses matched for age, year of surgery, tumor size, and Fuhrman grade addressed the effect of nephrectomy type (NSS vs RN) on CSM. Results: Five years after surgery, the surviving proportions of NSS and RN patients matched for age, tumor size, and year of surgery were respectively 91.4 and 95.3% and 90.1 and 93.8% in the cohort, where additional matching for Fuhrman grade was performed. Neither of the matched analyses resulted in statistically significant CSM difference (P = .1 and .4) between NSS and RN. Similarly, competing-risks regression analyses based on both matching schemes also failed to reveal statistically significant CSM differences (P = .3 and .3). Conclusions: Our study represents the largest and the only population-based analysis of cancer control efficacy of NSS vs RN in T1bN0M0 RCC. It indicates that NSS does provide equivalent cancer control relative to RN. In consequence, based on cancer control equivalence, NSS should be given equal consideration to RN in patients with T1bN0M0 lesions. Crown