Retrospective review of extra-pulmonary small cell carcinoma and prognostic factors.

Background: Extra-pulmonary small cell carcinoma (EPSCC) is a rare cause of malignancy, representing 2.5-5 % of all small cell carcinomas, with an incidence rate of 1000 cases per year in the USA. The purpose of this study is to characterize the location, extent of disease, and survival of patients with EPSCC, and to analyze potential clinical prognostic indicators predicting survival.