Prognostic Significance of CD151 Expression in Esophageal Squamous Cell Carcinoma with Aggressive Cell Proliferation and Invasiveness

CD151 is a member of the tetraspanins and has recently been reported as a promoter of the malignant progression of cancer. The purpose of this study was to clarify the clinicopathological outcome and prognostic significance of the immunohistochemical expression of CD151 in esophageal squamous cell carcinoma (ESCC). We evaluated the significance of CD151 expression by immunohistochemistry in 138 surgically resected ESCC and the association of CD151 expression with clinicopathological features. Seventy-five (51.7%) ESCC showed a positive expression of CD151, which indicated a significant association with tumor depth (P = 0.004), lymph node metastasis (P = 0.002), distant metastasis (P = 0.025), and lymphatic invasion (P = 0.046), as well as the Ki-67 labeling index (P = 0.011). The 5-year survival rate of ESCC patients with CD151-positive expression was significantly lower than with CD151-negative expression (positive, 43.1%; negative, 63.8%; P = 0.003). Multivariate analysis showed that positive CD151 expression was not an independent factor for poor survival (P = 0.096). CD151 expression is associated with tumor proliferation and invasiveness in ESCC.