Cytoreductive Nephrectomy In Metastatic Papillary Renal Cell Carcinoma: Results From The International Metastatic Renal Cell Carcinoma Database Consortium (Imdc).

581Background: There is evidence that cytoreductive nephrectomy (CN) may be beneficial in metastatic renal cell carcinoma (mRCC), but the role of CN in patients with papillary histology is unclear. Methods: Using the IMDC database, a retrospective analysis was performed on patients with papillary mRCC treated with or without CN. Baseline characteristics and IMDC risk factors were collected. Median overall survival (OS) was determined for both patient groups. Multivariable Cox regression analysis was performed to control for imbalances in individual IMDC risk factors. Results: In total, 353 patients with papillary mRCC with (n = 75) or without (n = 278) a component of clear cell histology were identified. Median follow-up time was 57.1 months (95% CI 32.9-77.8) and the OS from the start of first-line targeted therapy for the entire cohort was 13.2 months (95% CI 12.0-16.1). Baseline characteristics are in Table 1 and patients who had CN were more likely to be younger, with better KPS, and have sarcomatoid ...