Immunohistochemical study of androgen receptors in breast carcinoma. Evidence of their frequent expression in lobular carcinoma

Abstract

Androgens and androgen receptors (AR) are involved in the pathogenesis of breast cancer. Epidemiological studies have shown a significant association between the risk of breast cancer and androgens. However, the functional role and clinical value of AR expression in breast carcinoma have still not been clearly defined. The present study was set up to investigate the prevalence of ARs in a series of consecutive invasive breast carcinomas (IBCs) and to evaluate the patterns of AR phenotypes in a series of selected invasive lobular carcinomas (ILCs). Among the 250 consecutive IBCs (consisting of 212 ductal and 38 lobular neoplasms), AR immunoreactivity was observed in 151/250 (60.4%) cases, being expressed in 118/212 (56%) ductal and 33/38 (87%) lobular carcinomas (a statistically significant difference, chi2=11.82). AR expression was frequently associated with ER (65.2%, chi2=14.33) and PR positivity (66.9%, chi2=7.36). Most AR positive cases showed a low proliferative index (63.7%) and a low or intermediate histological grade (G1-G2, 63.9%). Among the 80 selected ILCs, AR expression was observed in 64/80 (80%) cases. Our results confirm that ARs are expressed in most breast cancers. Moreover, we demonstrated that AR positivity is particularly marked in lobular neoplasms. In addition, AR positive carcinomas are frequently characterized by a low or intermediate grade, a low proliferative index and ER and/or PR co-expression.

Androgen Receptor Levels and Association with PIK3CA Mutations and Prognosis in Breast Cancer

“…Androgen signaling may also activate estrogen-responsive genes (3,(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17). ER-negative and/or PR-negative breast cancers represent f30% of all breast cancers and are known to have a more aggressive clinical course, partly because these tumors are more likely to be poorly differentiated and of higher histologic grade (30,31).…”

Androgen receptors as a prognostic and predictive factor in breast cancer.

“…The clinical consequence of such influence of androgens on cell receptors is poor prognosis of those female patients receiving hormone therapy, whose cancer cells do not show AR expression. Many authors emphasize that expression of AR in breast tumors is a favorable prognostic factor, while the lack of AR correlates with a higher grade of malignancy [9][10][11][12].…”

An Immunohistochemical Panel to Differentiate Metastatic Breast Carcinoma to Skin From Primary Sweat Gland Carcinomas With a Review of the Literature

“…Numerous studies have evaluated these entities either individually [6][7][8][9][10][11][12][13][14][15] or comparatively using various (IHC) stains, [16][17][18][19][20][21][22][23] but there has been no study, to our knowledge, to determine the most useful IHC panel for differentiating CMBC from SGC.…”

“…16,24 Androgen receptor (AR), although often found in high-grade invasive breast cancer, has also been identified in some SGCs. [7][8][9]13 The basal cytokeratin stains (CK5, CK14, and CK17), recently shown to be expressed in the basal phenotype of breast carcinoma, were not present in most other types of PBC. 25,26 These stains have also been shown to be present in a few SGC cases.…”