Overexpression of the HER-2/neu oncogene in pancreatic adenocarcinoma

Novel systemic treatments are needed in pancreatic cancer. The authors soug ht to establish the frequency of overexpression of the HER-2/neu oncogene i n patients with pancreatic adenocarcinoma to determine the potential role o f trastuzumab (Herceptin) as a therapeutic agent in this disease. Tumor spe cimens from patients with pancreatic adenocarcinoma were analyzed by staini ng for p185(HER2) protein using the DAKO immunohistochemical assay. Patient s with and without HER-2/neu overexpression by immunohistochemistry were co mpared with respect to clinical and pathologic characteristics. HER-2/neu g ene amplification was also evaluated by fluorescence in situ hybridization (FISH). Thirty-two of 154 patients (21%) had pancreatic adenocarcinoma that demonstrated HER-2/neu overexpression by immunohistochemistry. At initial diagnosis, 16% of resectable cancers, 17% of locally advanced cancers, and 26% of metastatic cancers were determined to have HER-2/neu overexpression. Three of 11 (27%) patients with HER-2/neu overexpression by immunohistoche mistry had gene amplification by FISH. HER-2/neu overexpression occurs in a subset of pancreatic cancer. Evaluation of the efficacy of trastuzumab for patients with pancreatic cancer who overexpress HER-2/neu appears indicate d.