Amongst the four proteins, only cyclin D1 overexpression was significantly associated with poor recurrence-free survival (adjusted hazard ratio = 1.87; 95 % confidence interval = 1.12 – 2.69, P = 0.02) in adenocarcinoma but not in squamous cell carcinoma (P = 0.44). This evidence concerns the gene CCND1 and adenocarcinoma.