Androgen Receptor Expression in Triple Negative Breast Cancer - Study from a Tertiary Health Care Center in South India

Abstract

Abstract Background: The treatment of breast cancer is based on a multi-modality approach. Analysis of the hormone receptor has been accepted as a standard procedure, in the routine management of breast cancer patients. Triple negative breast cancers (TNBCs) are those which are negative for expression of all three markers, i.e., estrogen receptor, progesterone receptor (PR), and human epidermal growth factor receptor. High expression of Ki-67, a proliferation index, has been associated with a worse prognosis in TNBC. TN cancers are aggressive in nature as they do not respond to routine targeted therapy. The role of the androgen receptor (AR) in breast carcinomas is important as AR has been suggested as a potential therapeutic target. We did this study to assess AR immunoreactivity in TNBCs and correlate with Ki-67 index. Materials and Methods: In this study group, there were 45 cases of TN invasive breast carcinomas. These tumors were analyzed with respect to AR and Ki-67 index. Results: Of 45 TN breast carcinomas analyzed, 42 were infiltrating duct cell carcinoma (IDCC) of not otherwise specified type. There were one medullary and two metaplastic carcinomas. The median age was 46 years. AR was positive in 20% (9/45) of cases. All the AR positive cases were an IDCC (nos). Out of the nine AR positive cases, six showed positivity for Ki-67. The statistical analysis using Pearson's Chi-squared method did not reveal any correlation between AR and Ki-67 index (P = 0.574). Conclusion: Although our study did not reveal any statistically significant correlation between AR and Ki-67 index, assessment of AR status in TNBC patients is desirable as it may help to develop a targeted therapy in future in these aggressive cancers.