Breast Cancer Tumor Biology Characteristics and Its Correlation in a Tertiary Care Center

Abstract

Ab s t r Ac t Aims/Objectives: The study aims to evaluate and correlate the relationship between hormone receptor status—estrogen, progesterone receptor (ER and PR), and Herceptin receptor (Her-2/neu) with tumor characteristics in breast cancer patients. Materials and methods: The current study included 101 breast cancer patients of various age-groups from the period 2016–2020. The tumors were evaluated for hormone expression, size, histologic grade, lymphovascular invasion, and axillary node status. The excised breast tissue specimen was evaluated for hormone status by immunohistochemistry (IHC) testing on paraffin blocks and was further analyzed using the fluorescence in situ hybridization (FISH) technique as per requirement. Stratification based on hormone receptor status was done in four categories—ER+PR+Her-2neu−, ER−PR−Her-2neu+, ER+PR+Her-2neu+, and ER−PR−Her-2neu−. Results: In this study, 37.6% of tumors were ER+PR+Her-2neu−, 13.8% ER−PR−Her-2neu+, 13.8% ER+PR+Her-2neu+, and 34.6% ER−PR−Her2neu−. Among high-grade tumors, more than half (52%) patients were hormone receptor-negative, whereas among low-grade tumors 55% of patients were hormone receptor-positive. Sixteen percent of patients presented with a younger age-group (<35 years) and in these patients, nearly 38% were Her-2/neu positive and most of the Her-2/neu receptor-positive patients (80%) had lymphovascular space invasion. Primary tumor size at time of presentation was <2 cm (T1) in only 11% of cases and 2–5 cm (T2) in 72% of cases. Lymph node positivity did not correlate with hormone receptor status. Conclusion: The incidence of Her2-neu positive breast cancer patients was higher in the Indian population as compared to the Western world. The current study depicts the distinct shift in terms of tumor stage and biology, higher rate of Her-2/neu-positivity, younger age at diagnosis, larger tumor size, advanced tumor grade, and more positive lymph node involvement in contrast to the Western population.