Racial/ethnic differences in time to nephrectomy and its association with cancer-specific mortality in localized renal cell carcinoma

PURPOSE: Whether racial/ethnic differences exist in time to nephrectomy (TTN) and whether prolonged TTN differentially affects cancer-specific mortality (CSM) remains unclear. We evaluated race/ethnicity as a predictor of prolonged TTN and assessed race/ethnicity-specific associations between TTN and CSM in localized renal cell carcinoma (RCC). METHODS: Patients were identified within the Surveillance, Epidemiology and End Results database (2010-2021) and stratified according to race/ethnicity and TTN ≤ 3 vs. > 3 months. Multivariable logistic regression models, propensity score matching (PSM) and multivariable competing risks regression models were used. RESULTS: In 11,058 T1b-2 N0 M0 clear-cell RCC patients, TTN > 3 months was recorded in 1168 (15.6%) of 7506 Caucasians, in 505 (23.6%) of 2138 Hispanics, in 180 (26.6%) of 676 African Americans, and in 118 (16.0%) of 738 Asians and Pacific Islanders (API). Hispanic (OR 1.80, p < 0.001) and African American (OR 2.10, p < 0.001) race/ethnicity independently predicted higher proportions of TTN > 3 months, compared to Caucasian. Over the study span, the proportion of patients with TTN > 3 months increased significantly in all four racial/ethnic groups (all p < 0.01). After PSM, TTN > 3 months was associated with higher CSM in Caucasians (sHR 1.57, p < 0.001) and in Hispanics (sHR 1.55, p = 0.046), but not in African Americans or APIs. CONCLUSION: In localized RCC patients treated with nephrectomy, TTN > 3 months became more prevalent over time in all four examined racial/ethnic groups. In Hispanics and African Americans, TTN > 3 months proportions were higher than in Caucasians and APIs. TTN > 3 months was independently associated with higher CSM in Caucasians and Hispanics, but not in African Americans and APIs.