Histopathology of surgically treated renal cell carcinoma: survival differences by subtype and stage.

Abstract

Previous studies of the impact of renal cell carcinoma histopathology on survival are conflicting and generally limited to institutional analyses. Thus, we determined the role of renal cell carcinoma histopathology on the stage specific survival rate in a large population based cohort. We used the 2000 to 2005 National Cancer Institute SEER (Surveillance, Epidemiology and End Results) database to identify 17,605 patients who underwent surgery for renal cell carcinoma and met study inclusion criteria. Patients were stratified by histological subtype (clear cell, papillary, chromophobe, collecting duct and sarcomatoid differentiation) and pathological stage. We performed Cox proportional hazard modeling and Kaplan-Meier survival analysis to determine overall and cancer specific survival. Patients with papillary and chromophobe pathology were less likely to present with T3 or greater disease (17.6% and 16.9%, respectively) while patients with collecting duct and sarcomatoid variants were more likely to present with T3 or greater disease (55.7% and 82.8%, respectively) compared to those with clear cell histology (p <0.001). On multivariate analysis histology was significantly associated with overall and cancer specific survival. Patients with chromophobe pathology had improved survival (HR 0.56, 95% CI 0.40-0.78) while those with collecting duct and sarcomatoid variants had worse survival (HR 2.07, 95% CI 1.44-2.97 and 2.26, 95% CI 1.93-2.64, respectively). Renal cell carcinoma histological subtype predicts overall and cancer specific survival. Patients with collecting duct and sarcomatoid variants of renal cell carcinoma have poor survival, even those who present with low stage disease. These data suggest inherent differences in renal cell carcinoma biology and may ultimately form the basis of future histologically targeted therapies.