Treatment outcome and prognostic factors in renal cell cancer patients with bone metastasis

Abstract

We retrospectively analyzed treatment outcomes and factors for poor prognosis for patients with renal cell cancer (RCC) bone metastases. Patients with bone metastases at initial diagnosis of metastasis secondary from RCC, treated at our hospital between 1984 and 2009, were retrospectively reviewed and statistically analyzed. Among 214 RCC patients with metastasis, 71 patients (33%) were found to have bone metastases at initial diagnosis of metastasis. The median follow-up was 21.1 months (intra-quartile range: IQR, 9.1–47.4 months). The estimated median overall survival time from the diagnosis of bone metastasis was 27.7 months. The probability of patients surviving at 1, 2, and 5 years was 63.7, 52.2, and 19.3%, respectively. When they were stratified by MSKCC scores, the probability of the median overall survival of the populations classified as favorable, intermediate, and poor was not reached, 32.9, and 10.5 months, respectively (P = 0.002). In addition, poor performance status (PS) (hazard ratio [HR]: 1.938, P = 0.035) and no prior nephrectomy (HR: 3.008, P = 0.004) were extracted as independent poor prognostic factors by multivariate analysis. All treatment modalities—including radical en bloc surgery, radiation therapy, cytokine therapy, molecular targeted therapy, and administration of zoledronic acid—seemed to contribute to favorable survival. More than half of the patients with bone metastases secondary from RCC were predicted to survive more than 24 months. In this population, MSKCC scores were valid predictors of survival. With increased treatment options, RCC patients with bone metastasis may benefit further from subsequent modalities and/or agents.