METHODS: We analysed the expression of AR in 97 TNBC cases from Penang General Hospital for a period of 3 years (2014 to 2017). Androgen receptor immunoreactivity was considered positive if ≥ 1% of tumour cells nuclei were stained irrespective of staining intensity.
RESULTS: The prevalence of AR expression in TNBC was 31% (30/97), with the proportion of AR-positive tumour cells ranged from 1% to 90%. These include 23 invasive carcinomas, no special type (NST) and 7 other invasive carcinoma subtypes (papillary, lobular, clear cell and medullary carcinomas). Sixty-seven cases (69%) that showed AR immunonegativity were invasive carcinomas, NST (n=60), clear cell carcinoma (n=1) and metaplastic carcinoma (n=6). Androgen receptor immunoexpression was inversely correlated with tumour grade (p=0.016), but not the tumour stage, tumour size and nodal status.
CONCLUSION: AR is expressed in about one-third of TNBC and loss of AR immunoexpression does not predict adverse clinical outcomes. Larger cohorts for better characterisation of the role of AR immunoexpression in TNBC are warranted.