ObjectiveTo investigate the expression of Cyclin D1 in stage T2-3N0M0 esophageal squamous cell carcinoma (ESCC) and its relationship with patient prognosis. MethodsExpression of Cyclin D1 in 227 ESCC specimens at stage T2-3N0M0 was detected by immunohistochemistry (IHC). Receiver operating characteristic (ROC) curve analysis was performed to select the cut-off score for high or low IHC reactivity. Correlations between Cyclin D1 expression and clinicopathological features as well as prognosis of ESCC patients were determined. ResultsAmong the 227 patients, 90 (39.6%) patients had low expression of Cyclin D1, and 137 (60.4%) patients had high expression of Cyclin D1.No significant correlation was observed between Cyclin D1 expression and patient gender (P=0.298), age(P=0.525), tumor location (P=0.570), tumor length (P=0.056), tumor grade (P=0.713), and depth of invasion (P=0.557). There was significant difference in prognosis between low-expression Cyclin D1 group and high-expression Cyclin D1 group (3-year survival rate:51.1% vs. 43.8%, 5-year survival rate:43.3% vs. 30.7%, P=0.047). Cox proportional-hazards regression model analysis showed that Cyclin D1 was not an independent prognostic factor for ESCC patients at stage T2-3N0M0 (relative risk=1.378, 95% CI:0.990-1.919, P=0.057). ConclusionOver expression of Cyclin D1 may be an adverse prognostic factor of ESCC patients at stage T2-3N0M0.