Decreased androgen receptor expression is associated with distant metastases in patients with androgen receptor-expressing triple-negative breast carcinoma

To characterize prognostic values of androgen receptor (AR) in triple-negative (TN) breast cancers, we investigated AR expression status and levels, explored an association of AR expression with metastatic disease, and correlated AR expression with Ki-67 in TN invasive breast carcinomas. AR expression was analyzed with immunohistochemistry in 121 cases of TN tumors. Thirty-nine cases had distant metastatic disease and 82 had locoregional disease only. AR was positive in 38 (31.4%) of the 121 cases. Our results indicate that among the AR-positive TN tumors, distant metastases are significantly associated with lower expression of AR compared with cases with only locoregional disease, and that AR expression negatively correlates with Ki-67 expression. These findings suggest that decreased intratumoral AR expression may be predictive of distant metastatic disease and AR expression levels may have potential prognostic value in AR-expressing TN tumors.