Clinical significance of hypoxia inducible factor-1α expression on postoperative adjuvant radiotherapy in esophageal carcinoma

Abstract

Objective To determine the effects of hypoxia inducible factor-1α(HIF-1α) expression on postoperative adjuvant radiotherapy in esophageal carcinoma. Methods 95 cases with esophageal carcinoms who received radical operation were analyzed with followed-up data from 1995 to 1998.Expression of HIF-1α in 45 patients with esophageal carcinoma who received radiotherapy after radical operation were deternlined by immunohistochemical method in contrast with 50 patients with esophageal carcinoma received surgery alone.Kaplan-Meier method and COX proportional hazard model were used to analyze.Results The positive expression of HIF-1α in esophageal carcinoma was observed mainly in the nucleus of tumor cells.The positive expression rate of HIF-1α in esophageal carcinoma was 58.9%.The expression of HIF-1α had no relationship with age,sex,histologic subtype and T stage,but had positive relationship with recurrence and distant metastasis.There was significant difference between patients with positive and negative HIF-1α protein expression in surgery alone and postoperation radiotherapy group. COX model analysis showed that HIF-1α had separate and significant impacts on prognosis in surgery group and surgery plus radiotherapy group. Conclusion Over expression of HIF-1α protein suggests a poor prognosis,and has tendency to resist radiotherapy in esophageal carcinoma. Key words: Esophageal neoplasms; HIF-1α; Radiotherapy,computer-assisted; Adjuant radiotherapy; Prognosis