HER-2 overexpression (3+) in patients with squamous cell esophageal carcinoma correlates with poorer survival

The incidence of esophageal carcinoma is increasing worldwide. In Sweden, approximately 400 patients are diagnosed each year. The present study retrospectively investigates survival in 97 patients with esophageal carcinoma in regard to their HER-2 status as examined by immunohistochemistry (IHC) and chromogen in situ hybridization (CISH). Sixty-eight patients had localised disease and 29 patients had advanced disease. Seventy patients had squamous cell carcinoma, and nine of these patients (13%) had HER-2 overexpression (3+). Eight (30%) of 27 adenocarcinoma patients overexpressed (3+) HER-2. In patients overexpressing (3+) HER-2 a statistical trend towards poorer survival was observed (P = 0.057). In squamous cell carcinoma patients, HER-2 overexpression (3+) correlated with poorer survival (P = 0.035), whereas in adenocarcinoma patients, HER-2 status (3+) did not. HER-2 amplification according to CISH was present in five (two squamous cell carcinomas and three adenocarcinomas) out of 17 HER-2 overexpressing (3+) tumours. In conclusion, HER-2 overexpression (3+) seems to be associated with poorer survival in esophageal carcinomas, especially in patients with squamous cell esophageal carcinoma.