Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 58 5 2020 08 10 234 239 Ghazi Zafar Department of Histopathology, Chughtai Institute of Pathology, Lahore, Pakistan Sameen Afzal Department of Histopathology, Chughtai Institute of Pathology, Lahore, Pakistan. Asma Zafar Department of Histopathology, Chughtai Institute of Pathology, Lahore, Pakistan. Samina Zaman Department of Histopathology, Chughtai Institute of Pathology, Lahore, Pakistan. 2019 12 11 2020 04 27 Her-2 (ErbB-2) is an oncogene frequently overexpressed in breast and gastric adenocarcinomas, and anti-Her-2 targeted therapy can be given to such patients. Her-2 overexpression and role of anti-Her-2 targeted therapy in cases of gallbladder adenocarcinomas (GBC) are still debatable. Scoring protocols for Her-2 expression in breast and gastric carcinomas are standardized, however, not for carcinomas arising in other body organs like the gallbladder. This study is conducted to evaluate the expression of Her-2 in patients with GBC, which may benefit from targeted therapy. It is a cross-sectional study conducted on patients with GBC (n=63; 53 women and ten men). An automated immunohistochemical technique was used with an anti-ErbB2 antibody. Scoring was conducted according to the CAP (College of American Pathologists) criteria for breast cancer. Positive (3+) Her-2 staining was observed in 8/63 (12.7%). Nine cases (14.3%) showed equivocal staining (2+) pattern. All of the tumors showing Her-2 overexpression were moderately differentiated. This study indicates that a significant number of GBC cases show Her-2 overexpression. This subgroup may benefit from inhibitors of the Her-2 pathway. Standardization of scoring protocol for Her-2 expression in GBC is needed to better evaluate the predictive potential of Her-2 for the treatment of these tumors. https://acta.tums.ac.ir/index.php/acta/article/view/8213 https://acta.tums.ac.ir/index.php/acta/article/download/8213/5404