HER2 and gastric carcinomas: methods for gene status and protein expression determination

• Grant number: 11/18802-0
• Support Opportunities: Regular Research Grants
• Start date: April 01, 2012
• End date: March 31, 2015
• Field of knowledge: Health Sciences - Medicine - Pathological Anatomy and Clinical Pathology
• Principal Investigator: Maria Dirlei Ferreira de Souza Begnami
• Grantee: Maria Dirlei Ferreira de Souza Begnami
• Host Institution: A C Camargo Cancer Center. Fundação Antonio Prudente (FAP). São Paulo , SP, Brazil

Abstract

Gastric cancer is the second leading cause of cancer-related death worldwide. HER2 gene alterations are associated with the development and progression of various human neoplasms. In breast carcinomas, amplification of HER2 is found in about 20% of cases and treatment of patients with trastuzumab, a monoclonal antibody, has been quite effective. The success of this therapy depends mainly on a careful selection of patients who actually have some benefit from this treatment, avoiding unnecessary expense and undesirable side effects. In gastric carcinomas, amplification of HER2 has been reported at a frequency of 7 to 27% of cases. This variability is mainly due to the different methodologies used for studying the expression and / or gene amplification. It is an unquestionable need for standardization in research and interpretation of HER2 expression and amplification in gastric carcinoma to define the best material (primary or metastatic tumor) to be searched, the better antibody, clone and score interpretation that best correlates with amplification gene. Therefore, the purpose of this work is to research the expression and HER2 amplification in 662 gastric carcinomas by immunohistochemistry, Dual ISH and FISH to determine the best methodology for studying the expression and HER2 amplification in gastric carcinoma, thus contributing to the proper selection of patients will actually benefit from the use of trastuzumab. (AU)