Clinicopathological and prognostic role of cyclin D1 in esophageal squamous cell carcinoma: a meta-analysis

Cyclin D1 is one of the most commonly over-expressed oncogenes; however, its role in esophageal squamous cell carcinoma (ESCC) remains controversial. We conducted a meta-analysis of 20 studies, comprising 2,041 patients to clarify this issue. In all studies, paraffin-embedded surgical specimens were collected and the status of cyclin D1 was determined by immunohistochemistry (IHC). The combined odds ratios (Ors) for cyclin D1 expression were 0.74 (95% confidence interval [CI]: 0.58-0.93) for well and moderately differentiated versus poorly differentiated tumors, 0.65 (95% CI: 0.45-0.94) for T1/T2 versus T3/ T4 tumors, 0.59 (95% CI: 0.39-0.90) for N0 versus N1 tumors, and 0.48 (95% CI: 0.33-0.71) for stage I/II versus stage III/IV diseases, respectively. The association between cyclin D1 expression and prognosis was examined in 10 studies, and the combined hazard ratio was 1.78 (95% CI: 1.49-2.12). Cyclin D1 expression level detected by IHC is associated with worst clinicopathological features and prognosis for ESCC.