title: HER-2 status in gastrointestinal stromal tumor.
abstract: Human epidermal growth factor receptor-2 (HER-2) encodes for the transmembrane glycoprotein HER-2 that is involved in activation of intracellular signal transduction pathways that control cell growth and differentiation. HER-2 is overexpressed in approximately 20% of patients with breast cancer and has been associated with poorer prognosis. Since 1998, the anti-HER-2 antibody trastuzumab has been used for the treatment of patients with HER-2-positive breast cancers. However, little information is available about the relationship between HER-2 and gastrointestinal stromal tumors. This study's purpose was to determine the HER-2 status in gastrointestinal stromal tumors. We found that all 477 cases included in this study were negative (score 0) by immunohistochemistry using HercepTest, and no HER-2 gene amplification was detected in 71 cases submitted to fluorescence in situ hybridization. These results show that HER-2 may not have any role in gastrointestinal stromal tumor pathogenesis and that the neoplasm may not be suitable for treatment with trastuzumab.
authors.affiliation: Consultoria em Patologia, Botucatu, Sao Paulo, Brazil Department of Pathology, University of Sao Paulo Medical School, Sao Paulo, SP, Brazil.
authors.forename: Lisandro Ferreira
authors.initials: LF
authors.lastname: Lopes
authors.affiliation: Consultoria em Patologia, Botucatu, Sao Paulo, Brazil Department of Pathology, University of Sao Paulo Medical School, Sao Paulo, SP, Brazil. Electronic address: bacchi@consultoriapatologia.com.br.
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Bacchi
mesh_terms: D046152:Gastrointestinal Stromal Tumors / Q000235:genetics*; D018628:Gene Dosage; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*; D046888:Tissue Array Analysis
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases