Small cell carcinoma of the upper urinary tract and factors associated with progress survival: a systematic review and pooled analysis.

INTRODUCTION: Little is known about small cell carcinoma of the upper urinary tract (UUT-SCC), the aim of this study is to identify the risk factors in relation to survival of patients with UUT-SCC. EVIDENCE ACQUISITION: Literature search on UUT-SCC was performed in databases including MEDLINE, EMBASE, Wangfang, and CNKI. Studies were eligible for inclusion if outcomes of patients with histopathologically confirmed UUT-SCC were reported. The relevant data on clinic, pathology, and therapy were collected. Progress survival was evaluated using the Cox regression model with the robust sandwich estimates of the covariance matrix. EVIDENCE SYNTHESIS: There were 55 eligible publications identified, contributing 76 patients in total. The median of overall survival (OS) was 14 months. In univariable analyses, pathological stage and platinum-based chemotherapy regimen were associated with OS (pT3-pT4 versus pT1-pT2, HR=3.228, P=0.005; other chemotherapies versus platinum-based, HR=6.249, P=0.035). The median of cancer-specific survival (CSS) was 15 months. In univariable analyses, pathological stage and platinum-based chemotherapy regimen were associated with CCS (pT3-pT4 versus pT1-pT2, HR=3.332, P=0.004; non-platinum based versus platinum-based, HR=7.784, P=0.025). CONCLUSIONS: In multivariable analyses, no variables were associated with OS and CSS. UUT-SCC is a rare tumor characterized by an aggressive clinical course. Pathological stage and platinum-based chemotherapy regimen are the most important factors related to OS and CSS.