Expression of Androgen receptor in Primary Breast Carcinoma and its Association with Hormone Receptor Status and Molecular Subtypes

Abstract

Background: Breast cancer is the second most common malignancy in Indian women. The role of estrogen and progesterone receptors (ER and PR) is well established in predicting the prognosis and management of therapy. However, the role of androgen receptor (AR) expression is unclear in the Indian context. This study aims to evaluate the expression of AR in breast cancer and to find its association with clinicopathological parameters and hormone receptor status like ER, PR, HER2/neu and Ki 67 and also molecular subtypes of breast cancer. Materials and Methods: A retrospective study included 64 patients of histopathologically proven breast cancer with known hormone receptor and Ki 67 status. Demographic and histopathologic details were retrieved. Immunohistochemistry for AR was done and was correlated with clinicopathological parameters and hormone receptor status, Ki 67 status and molecular subtypes of breast cancer to find its association. P value <0.05 was considered significant. Results: AR expression was noted in 67.2% of the cases. Out of 42 ER positive and 33 PR positive cases, 34 (81%) and 27 (81.8%) showed AR expression respectively. AR positivity was noted in 30.8% of triple‑negative tumors. AR expression was significantly associated with ER (P=0.001 ), PR (p=0.010), Luminal B (P=0.002) and triple negative cancer patients (p =0.003). No significant association was found with pathological parameters studied like laterality, tumor size, histological type, grade, lymphovascular invasion and lymph node status. Conclusion: We conclude that breast cancer express AR which is significantly associated with ER and PR and is significantly expressed in Luminal B and triple negative cases. Since a subset of triple negative cases showed positive AR expression, further studies are required to determine whether AR could be of therapeutic target in these patients.

Keywords

• androgen receptor
• estrogen receptor
• triple negative
• breast cancer
• hormone status
• molecular subtypes