Relationship of ER, PR, HER2 / neu with Other Prognostic Factors in Breast Cancer along with the Role of Androgen Receptor in Triple Negative Breast Cancer

Abstract

BACKGROUND Understanding various risk factors associated with breast cancer can help in early identification & prompt treatment of patients with breast cancer. Apart from clinical parameters like age, disease presentation and menopausal status, important prognostic indicators in histopathology are size and extent of tumour, histologic type,histologic grade and lymph node status. Also, there are other factors which are not only predictive of outcome, but also direct therapies against particular molecular targets. These factors are oestrogen receptor (ER) status, progesterone receptor (PR) status, HER2 / neu status, Ki-67 proliferation index & androgen receptor (AR) status. We wanted to analyse various hormone receptors & their correlation with prognostic factors. In addition, androgen receptor expression is also studied in triple negative breast cancer cases. METHODS The study included 50 cases over a period of 18 months from January 2018 to June 2019 received in the Department of Pathology, Gandhi Medical College, Bhopal, India. These cases were subjected to histopathological & immunohistochemistry (IHC) evaluation. RESULTS Among the 50 cases studied, the most common subtype was infiltrating ductal carcinoma (NOS - no special type, 84 %). Majority of patients were ER, PR, HER2 / neu negative (48 %) and among those triple negative cases, 25 % of cases were androgen receptor positive. CONCLUSIONS Expression of the hormone receptor (ER and PR) and HER2 status may provide significant information in directing patient management. Since traditional pathological methods and IHC remain standard for guiding the use of treatment, clinicians may be challenged with equivocal results that directs towards additional testing for definitive diagnosis and, better patient outcome. The most used therapy for advanced breast cancers is based on the use of AR antagonists, such as bicalutamide and enzalutamide, first- and second-generation AR antagonists respectively. Gene signatures, bioinformatics, and other clinical trials are also beneficial for clinician in estimating the benefits expected from adjuvant chemotherapy. KEY WORDS Breast Cancer, Oestrogen Receptor, Androgen Receptor, Triple Negative