Prognostic model for survival in patients with metastatic renal cell carcinoma: results from the international kidney cancer working group.

Purpose: To develop a single validated model for survival in metastatic renal cell carcinoma (mRCC) using a comprehensive international database.

Experimental Design: A comprehensive database of 3,748 patients including previously reported clinical prognostic factors was established by pooling patient-level data from clinical trials. Following quality control and standardization, descriptive statistics were generated.