Value of tumor size in predicting survival from renal cell carcinoma among tumors, nodes and metastases stage 1 and stage 2 patients.

Results in the literature are inconsistent regarding the value of tumor size in predicting survival from renal cell carcinoma, and its use as a staging variable in the current tumors, nodes and metastases system has been questioned. In this study tumor size had no prognostic significance in Kaplan-Meier or Cox regression models examining survival differences between 93 patients with stage T1N0M0 and T2N0M0 renal cell carcinoma dichotomized by tumor size cutoffs at 2.5, 5, 7.5 or 10 cm. In multivariate Cox regression models for 122 patients with stage T1NallMall or T2MallMall renal cell carcinoma, metastatic disease was the strongest predictor of survival, and patients with smaller tumors had significantly longer survival than those with larger tumors at all cutoffs except 2.5 cm., for which differences were insignificant. A 5 cm. cutoff maximized the value of tumor size in predicting survival. If tumor size is to remain the variable by which tumors, nodes and metastases stages T1 and T2 disease are differentiated, a 5 cm. cutoff should replace the current 2.5 cm. definition.