REG Iα is a reliable marker of chemoradiosensitivity in squamous cell esophageal cancer patients

Background: A reliable marker of chemoradiosensitivity that would enable appropriate and individualized treatment of thoracic squamous cell esophageal cancer has long been sought. We investigated whether regenerating gene (REG) I alpha is such a marker. Methods: We assessed expression of REG I alpha in untreated endoscopic biopsy specimens and examined the correlation between REG I alpha expression and the clinical responses to definitive chemoradiotherapy and prognosis. We also examined the relationship between REG I alpha expression in the resected tumor and the prognosis of patients who received esophagectomy for thoracic squamous cell esophageal cancer. Results: Among the 42 patients treated with definitive chemoradiotherapy, 8 of the 23 REG I-positive patients (35%) showed complete responses to chemoradiotherapy, while only one of the 19 REG I-negative patients did so. The survival rate among the REG I-positive patients was significantly better than among the REG I-negative patients. For the 76 patients treated surgically, there was no significant difference in the survival rates among the REG I-positive and REG I-negative patients. Conclusions: REG I alpha expression in squamous cell esophageal carcinoma may be a reliable marker of chemoradiosensitivity. We anticipate that it will enable us to provide more appropriate and individualized treatment to patients of advanced esophageal squamous cell carcinoma.