Ethnic Differences in the Expression of Her2/neu phenotype among women with breast cancer

Abstract

Background: Her2/neu plays a vital role in the management of breast cancer. Studies have shown differences in the expression of her2/neu as per ethnicity. Objectives: To assess the association of HER2/neu positive breast cancer with various ethnicities in Karachi, Sindh, Pakistan. Methodology: A prospective observational study was conducted at the Department of Oncology, Jinnah Postgraduate Medical Centre between June 2019 to January 2022. All patients referred to the oncology department from the outpatient department and emergency department for the management of breast cancer were eligible to partake in the study. Diagnosis of breast cancer was made on histopathology. Patients' socio-demographics including age, gender, occupation, education, ethnicity (Urdu speaking, Sindhi, Punjabi, Balochi, Pushtoons, and others), and clinical parameters including the site of the tumor, stage, and grade at presentation, and first-line treatment were documented. Results: A total of 550 patients were included. Overall her2neu positivity was seen at the rate of 34.7%(191/550), however as per ethnicity he2neu expression was the most in Pushtoons at the rate of 44.9%, with significant differences seen between the Pushtoons and the Balochis (p= <0.05). Conclusion: We found the highest rate of HER2neu positivity in Pushtoons and the least in Balochis, however further studies are warranted in larger study populations.