The prognostic effect of metastasis patterns on overall survival in patients with distant metastatic bladder cancer: a SEER population-based analysis.

Abstract

The prognostic impact of different distant metastases pattern in bladder cancer is unexplored still now. The aim of this study is to investigate the impact of different distant metastases pattern on the survival of patients with stage IV bladder cancers. A SEER analysis was performed and the overall survival was calculated by the Kaplan-Meier method. Multivariable Cox regression models were used to further analyze survival outcome and other prognostic factors. A total of 90,382 eligible cases were retrieved in the Surveillance, Epidemiology, and End Results database. Among these patients, stage of IV bladder cancer accounted for 7.03% (6354/90382) at initial diagnosis. Patients who suffered metastasis occupied 35.51% (2256/6354). Comparing with other three single metastases, the patients with liver metastasis exhibited worst OS whose mean of survival was 7.118months. Multivariate analysis with Cox hazard regression model showed that metastatic site was an independent prognostic factor of OS in patients with single metastasis (P < 0.05). The results of univariate survival analysis showed that metastatic pattern, sex, age, race, tumor stage, N-classification, differentiated grade, histological type, chemotherapy, radiotherapy and insurance status were not significantly correlated with overall survival of patients with two or three metastatic sites (all, P > 0.05). Bone was the most common site of single metastasis for bladder cancers. Patients with liver metastasis had worse survival outcome comparing with other three distant metastases. Knowledge of these differences in metastatic patterns might help to better guide pre-treatment evaluation of bladder cancer and make determination regarding curative-intent interventions.