Androgen Receptor Positive Breast Cancers Are Associated with Better Prognosis Compared with Androgen Receptor Negative Cancers
Hope T Richard, Joseph P Bergeron, Jorge A Almenara, Michael O Idowu. Virginia Commonwealth University, Richmond, VA
Background: Androgen receptor (AR) status has been suggested to be of potential prognostic as well as therapeutic importance in post-menopausal breast carcinoma patients. However, few studies have examined the association of AR with triple negative breast cancer, distant metastasis, and loco-regional recurrence. This study evaluated the relationship between AR status and the rate of distant metastasis, triple negative breast cancers, loco-regional recurrence, ER status, and axillary lymph node status.
Design: The clinical outcomes and pathologic characteristics of breast carcinoma cases from 1992 to 2008 were reviewed. A minimum of 5 years of follow-up was required for inclusion of cases without recurrence or metastases. For each case, tissue microarrays (TMA) were created by obtaining 1 mm cores in triplicate from different areas of the tumor using an automated TMA system (Beecher ATA-27). The specimens were stained with a mouse monoclonal antibody to androgen receptor (Dako, USA). Each case was reviewed independently by two pathologists, and cases with moderate to intense nuclear staining were considered positive. Statistical significance was determined using a Chi-squared test.
Results: Of 279 cases, 82 were found to have distant metastases and 30 had loco-regional recurrence. The median follow-up period for all cases was 72 months, and ranged from 12 to 228 months. AR positive cases were associated with a decreased incidence of distant metastases when compared to AR negative tumors (48 vs 34, p= 3.3 x 10e-6). Additionally, AR negativity was associated with high Ki67 (>30%), triple negative hormone receptor status, and high histologic grade. Interestingly, a greater percentage of AR positive tumors were more likely to have lymph node metastases at the time of diagnosis (76 vs 37, p=0.16), although it was not statistically significant. No significant difference in the effect of AR status was noted between patients greater than or less than 55 years of age.
|AR pos||AR neg|
|% distant mets (n=82)||41% (34)||59% (48)|
|% local recur (n=30)||43% (13)||57% (17)|
|% grade III (n=104)||33% (34)||67% (70)|
|% high Ki67 (n=94)||30% (28)||70% (66)|
|% triple neg (n=73)||16% (12)||84% (61)|
|% ER pos (n=181)||85% (153)||15% (28)|
|% LN pos (n=113)||67% (76)||33% (37)|