Prognostic factors and value of adjunctive nephrectomy in patients with stage IV renal cell carcinoma. We reviewed 57 cases of Stage IV renal cell carcinoma to clarify the factors influencing prognosis and to evaluate the value of nephrectomy. Cumulative survival from the initial diagnosis was analyzed with respect to the patients' age, sex, side of primary tumor, initial performance status (PS), site of metastasis, and nephrectomy. Overall survival for the patients was 51 percent at one year, 22 percent at three years, and 11 percent at five years. Age, sex, and side of primary tumor had no influence on survival. Improved survival was correlated with good PS, metastases limited to single organ, and removal of the primary tumor. With regard to histopathologic features in nephrectomized patients, low grade and stage were correlated with longer survival. These factors should be considered in the analysis of results of future clinical trials of metastatic renal cell carcinoma. 