Androgen Receptor Expression in Different Molecular Subgroups of Breast Cancer and Its Significance

ObjectiveTo evaluate the expression of AR (androgen receptor,AR) in different molecular subgroups of breast cancer and its significance. Methods Three hundred and thirty-five cases of invasive ductal breast carcinoma were involved in this study. Immunohistochemical expression of AR on paraffin-embedded tumor tissues was analyzed，compared with patients' outcome during 66-months' follow-up observation，and its implications were evaluated in five molecular subgroups. Results A greater percentage (72.5%) of breast cancer cases displayed nuclear immunoreactivity for AR，and AR expression was found in 53.2% of ER，PR-negative cases. The majority (61.0%) of basal-like breast cancers showed loss of AR expression，which had poor prognosis. In luminal A，luminal B，basal-like，and normal-like subgroups，the occurrence rate of relapse，metastasis and death for AR positive was lower than that of AR negative tumors (P=0.019，0.044，0.034 and 0.032 respectively). The disease-free survival curves also revealed that the patients with AR expression had a more favorable prognosis than those without it (P=0.006，0.013，0.036 and 0.010). Conclusion The detection of AR may help improve the molecular subtyping of breast cancer and provide theoretical evidence for individualized treatment.