Histological Subtype is an Independent Predictor of Outcome for Patients With Renal Cell Carcinoma

Purpose: There are significant differences in clinicopathological features among renal cell carcinoma histological subtypes but controversy exists regarding the independent impact of histological subtype on patient outcome after nephrectomy. We examined the significance of histological subtype on progression to distant metastasis and cancer specific death after nephrectomy. Materials and Methods: In a retrospective review of our institutional nephrectomy registry we identified 3,062 patients treated surgically for clear cell, papillary or chromophobe renal cell carcinoma between 1970 and 2003. Results: We identified 2,466 patients (80.5%) with clear cell, 438 (14.3%) with papillary and 158 (5.2%) with chromophobe renal cell carcinoma. There were significant differences in age at surgery, gender, symptoms at presentation, tumor size, stage and grade, tumor necrosis, sarcomatoid differentiation and multifocality among the 3 renal cell carcinoma subtypes (p <0.01 for all). A significant difference in metastasis-free and cancer specific survival existed between patients with clear cell renal cell carcinoma and the 2 other subtypes, although no significant difference in these outcomes was identified between patients with the papillary and chromophobe subtypes. The clear cell renal cell carcinoma subtype remained a significant predictor of metastasis (HR 2.76, 95% CI 2.05-3.73) and cancer specific death (HR 1.77, 95% CI 1.38-2.26, each p <0.001) after multivariate adjustment for the features listed above. Conclusions: Histological subtype is an independent predictor of progression to distant metastasis and cancer specific death in patients with renal cell carcinoma.