Prognostic Factors for Survival in Patients Undergoing Surveillance After Cytoreductive Nephrectomy.

ABSTRACT

PURPOSE: The clinical course of patients being placed on surveillance in a cohort of systemic therapy-naïve patients who undergo cytoreductive nephrectomy is not well documented. Thus, we evaluated the clinical course of patients placed on surveillance following cytoreductive nephrectomy and identified predictors of survival. MATERIALS AND METHODS: In this large single-institution study, we retrospectively analyzed metastatic renal cell carcinoma patients who underwent cytoreductive nephrectomy followed by surveillance. Predictors of survival were evaluated using the Kaplan-Meier method with a log-rank test. Patients were risk stratified based on IMDC (International mRCC Database Consortium) and number of metastatic sites (Rini score), with IMDC score ≤1 and ≤2 metastatic organ sites considered favorable risk. Primary end point was systemic therapy-free survival. Secondary end points included intervention-free survival, cancer-specific survival, and overall survival. RESULTS: Median systemic therapy-free survival was 23.6 months (95% CI 15.1-40.6), intervention-free survival was 11.8 months (95% CI 8.0-18.4), cancer-specific survival was 54.2 months (95% CI 46.2-71.4), and overall survival 52.4 months (95% CI 40.3-66.8). Favorable-risk patients compared to unfavorable-risk patients had longer systemic therapy-free survival (50.6 vs 11.1 months, P < .01), survival (25.2 vs 7.3, P < .01), and cancer-specific survival (71.4 vs 46.2 months, P = .02). CONCLUSIONS: Using risk stratification based on IMDC and number of metastatic sites, surveillance in favorable-risk patients can be utilized for a period without the initiation of systemic therapy. This approach can delay patients' exposure to the side effects of systemic therapy.