Background: Gastric cancers are the fifth most common cancer and the third most common cause of cancer mortality, in which adenocarcinoma tops the list. Human epidermal growth factor receptor 2 (Her2/neu), a proto-oncogene on amplification leads to various human cancers, namely breast, colon, cervical, endometrial, urothelial and recently discovered gastric adenocarcinoma.

Material and Methods: A prospective study was conducted in the Department of Pathology of a tertiary care hospital, Bhubaneswar, Odisha from January 2015 to December 2017. Endoscopic, total, distal and partial gastrectomy specimens were included after clinico-radiological data collection. The exclusion criterion was biopsies received post neo-adjuvant therapy.

Her2/neu immunohistochemistry (IHC) was conducted on all the adenocarcinoma of gastric/ gastro-esophageal location and was scored as 0, 1+, 2+ and 3+ (absent, mild, moderate and strong positivity).

Observation: It was found that gastric antrum was the commonest location followed by body and gastroesophageal junction. According to histological types, classical intestinal type showed maximum Her2/neu positivity followed by papillary, signet ring cell type while diffuse type showed least positivity.Though most of the strong Her2/neu adenocarcinomas were well differentiated type but majority of them presented with lymphnode metastasis.

Conclusion: In developing countries, the mortality due to gastric adenocarcinoma is high. The study aims at the prevalence of Her2/neu positivity in various sites, types, grade and stage of gastric adenocarcinomas to facilitate the institution of targeted therapy (anti-Her2/neuAb, Transtuzumab) in order to see its effect on patients’ morbidity and mortality.

Keywords: Gastric Adenocarcinoma, Her2/neu, Transtuzumab.

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Dr Kaushambi Chakraborty

Senior Resident, Department of Pathology, ESI-PGIMSR, Medical College & Hospital, Joka, Kolkata