Differences in Survival of Clear Cell Metastatic Renal Cell Carcinoma According to Partial vs. Radical Cytoreductive Nephrectomy

We tested within a large population-based and matched analyses if previously described advantages in othercause mortality (OCM) for clear cell metastatic renal cell carcinoma (ccmRCC) patients undergoing partial cytoreductive nephrectomy (PCN) still apply, relative to radical cytoreductive nephrectomy (RCN). We confirm the existence of OCM advantage after PCN vs. RCN in contemporary ccmRCC patients and PCN may continue being considered as a valuable alternative to RCN, when technically feasible. Background: It is unknown whether previously reported other-cause mortality (OCM) advantage of partial cytoreductive nephrectomy (PCN) vs. radical cytoreductive nephrectomy (RCN) still applies to contemporary clear cell metastatic renal cell carcinoma (ccmRCC) patients. Materials and Methods: We relied on the Surveillance, Epidemiology and End Results (SEER) database (2004-2019) to identify ccmRCC patients treated with PCN and RCN. Temporal trends of PCN rates within the SEER database were tabulated. After propensity score matching (PSM), cumulative incidence plots depicted 5-year OCM and cancer-specific mortality (CSM) of PCN and RCN patients. Multivariable Cox regression models tested for differences between PCN vs. RCN. Results: Of 5149 study patients, 237 (5%) underwent PCN vs. 4912 (95%) RCN. In the SEER database 2004 to 2019, rates of PCN in ccmRCC patients increased from 3.0% to 8.0% (estimated annual percent change [EAPC]: 3.0%; P = .04). After PSM, 5-year OCM rates were 2.4 vs. 7.5% for respectively PCN vs. RCN patients (P = .036). 5-year CSM rates were 50.8 vs. 53.6% for respectively PCN and RCN patients (P = .57). In multivariable Cox regression models, PCN was associated with lower OCM (Hazard Ratio (HR): 0.39; 95% confidence interval (CI): 0.18-0.84; P = .02) but did not affect CSM rates (HR: 0.99; 95% CI: 0.76-1.29; P = .96). Conclusions: We confirm the existence of OCM advantage after PCN vs. RCN in contemporary ccmRCC patients.