Low Expression of Bax Predicts Poor Prognosis in Patients with Locally Advanced Esophageal Cancer Treated with Definitive Chemoradiotherapy

Purpose: The present study evaluated the prognostic significance of apoptosis-related proteins, p53, Bcl-2, Bax, and galectin-3 in patients with locally advanced esophageal cancer treated with definitive chemoradiotherapy. Experimental Design: A total of 63 patients with locally advanced esophageal cancer (squamous cell carcinoma: 62; adenocarcinoma: 1; stages II-IV) were treated with definitive chemoradiotherapy using 5-fluorouracil and cisplatin combined with radiotherapy. Pretreatment tumor biopsy specimens were analyzed for p53, Bcl-2, Bax, and galectin-3 expression by immunohistochemistry. Results: High expression of Bax, p53, Bcl-2, and galectin-3 was observed in 67%, 47%, 24%, and 29% of patients, respectively. The median overall survival (OS) of total patients was 14 months with 16% of 3-year OS. High expression of p53, Bcl-2, and galectin-3 did not show correlation with clinicopathologic characteristics, including patient outcome. Low expression of Bax was significantly correlated with lack of clinical complete response ( P = 0.023). Low expression of Bax was also associated with poor OS (median, 8 months versus 16 months; P = 0.0008) in univariate analysis. In multivariate analysis, low expression of Bax was the most significant independent predictor of poor OS ( P = 0.009), followed by low dose intensity of cisplatin and lack of clinical complete response. Conclusions: Low expression of Bax was significantly associated with the poor survival of patients with locally advanced esophageal cancer treated with chemoradiotherapy using 5-fluorouracil and cisplatin. Immunohistochemical staining for Bax with a pretreatment biopsy specimen might be useful to select the optimal treatment options for these patients.