Introduction: Trastuzumab has been recently proposed as a treatment for patients with HER2-positive advanced/metastatic gastric cancer. Since most patients have inoperable disease at diagnosis, accurate assessment of HER2 status on biopsy specimens is essential to select the patients who may benefit from therapy.
Objective: Evaluate the immunohisto chemical expression of HER2 in gastric cancer from biopsies, surgical resection specimens, and evaluate their correlation with currently known clinical and histopathological prognostic factors.
Materials and Methods: Samples from 52 patients of both sexes and all age groups diagnosed with gastric cancer were analyzed. Immunohisto chemistry was performed using the HER2 antibody, and its evaluation was made, taking into account incomplete basolateral staining or only lateral staining.
Results: HER2 over expression was confirmed in 14(27.6 %) cases of which 13(93.8 %) cases were of intestinal type whereas only 1(6.2 %) case of diffuse type adenocarcinoma. There was no difference in HER2 over expression in relation to the age, gender, tumor site, tumor differentiation and stage.
Conclusion: As anti-HER2 therapies are becoming the standard of care in gastric cancer, currently available data indicate that IHC should be used as the screening test, and the pathologist has an important role to ensure an accurate testing of HER2 status in these tumors. HER2 over expression is more prevalent in the intestinal sub type. The relatively high percentage of HER2 positive tumors may provide a useful target for immunotherapy of these cancers.
Gastric Adenocarcinoma, IHC, Transtuzumab