| Abstract: | Gamma‐glutamyltransferase (GGT) is a membrane‐bound enzyme involved in the glutathione metabolism. Studies suggested that GGT was a marker of apoptotic balance and modulated tumor progression, invasion and drug resistance. Recently, GGT was shown to be associated with the progression of high‐grade esophageal epithelial dysplasia to invasive carcinoma. This study was conducted to investigate the value of pre‐therapeutic serum GGT levels as prognostic parameter in esophageal squamous cell carcinoma. Six hundred thirty‐nine resectable esophageal squamous cell carcinoma patients were recruited in this study and were stratified into two GGT risk groups. The association of pre‐therapeutic serum GGT levels and clinical–pathological parameters was examined. Univariate and multivariate survival analyses were performed. GGT serum levels were associated with gender, smoking status, TNM stage and lymph node involvement. Higher pre‐therapeutic serum GGT was found in males, smoker, advanced TNM stage and lymph node positive patients. Patients assigned to the low‐risk group had higher 5‐year overall survival rate (53.1% vs. 33.0%, P < 0.01) and disease‐free survival rate (45.2% vs. 23.4%, P < 0.01) than the high‐risk group. Patients with high‐risk group of GGT had 1.568 (95% confidence interval CI], 1.259 ∼ 1.952) times the risk of death and 1.582 (95% CI, 1.286 ∼ 1.946) times the risk of disease recurrence contrast with those with low‐risk group of GGT. The pre‐therapeutic serum GGT is a novel independent prognostic parameter for disease‐free survival and overall survival in resectable esophageal squamous cell carcinoma. |
