HER-2 status in gastrointestinal stromal tumor.
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.
Lopes
Lisandro Ferreira
LF
Consultoria em Patologia, Botucatu, Sao Paulo, Brazil Department of Pathology, University of Sao Paulo Medical School, Sao Paulo, SP, Brazil.
Bacchi
Carlos E
CE
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.
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
D018719:Erb-b2 Receptor Tyrosine Kinases