Prognostic factors in a large multi-institutional series of papillary renal cell carcinoma.

OBJECTIVES To investigate cancer-related outcomes and prognostic factors of papillary renal cell carcinoma (pRCC) in a large multicentre data set. Oncological outcome and prognostic factors of pRCC have been limitedly evaluated in comparison with the most common RCC subtype, clear cell RCC. PATIENTS AND METHODS From a multicentre retrospective database, including 5463 patients who were surgically treated for RCC at 16 Italian academic centres between 1995 and 2007, 577 patients with pRCC were identified. Univariable and multivariable Cox regression models were performed to identify prognostic factors predictive of recurrence-free survival (RFS) and cancer-specific survival (CSS) after surgery. RESULTS At a median (interquartile range) follow-up of 39.2 (21.7-72) months, 81 (14%) patients had experienced disease progression and 63 (11%) patients had died from disease; the 5-year RFS estimate was 85.5%. In multivariable analysis, pathological N stage (pooled P < 0.001), M stage (hazard ratio, 2.9; P = 0.007) and Fuhrman nuclear grade (pooled P = 0.039) were all independent predictors of RFS; the 5-year CSS estimate was 87.9%. In Cox multivariable analysis, an independent predictive role was reconfirmed for mode of presentation (pooled P = 0.038), pathological N stage (pooled P < 0.001), M stage (hazard ratio, 2.4; P = 0.049) and Fuhrman nuclear grade (pooled P = 0.037). CONCLUSIONS Patients with pRCC have a low risk of tumour recurrence and cancer-related death after surgery. Fuhrman nuclear grade was found to be a stronger predictor of both RFS and CSS, whereas only a non-statistically significant trend was found for the 2009 pathological T stage.