Antiandrogen therapy in metastatic male breast cancer: results from an updated analysis in an expanded case series.

Abstract

Male breast cancer is a rare disease treated as hormone receptor-positive female breast cancer. The characterization of breast cancer at the molecular level has lately revealed gender-related differences. As the androgen receptor is emerging as a potential oncogenic driver in male breast cancer, we analyzed efficacy data from metastatic patients treated with antiandrogens. We evaluated the activity of cyproterone acetate, either as a monotherapy or combined with a GnRH analog, in 36 metastatic male breast cancer patients. Fourteen patients were treated with cyproterone acetate as monotherapy and 22 patients with complete androgen blockade. We recorded 4 complete responses and 15 partial responses, for an overall response rate of 52.8 % (95 % CI, 36.5-69.4). Stable disease was reported in 11 patients. Median PFS was 8.9 months (95 % CI, 6.1-11.7), and median OS was 24.3 months (95 % CI, 22.5-26.1). Data on androgen receptor expression were available for 7 patients. All the 4 patients with androgen receptor-expressing tumors had a clinical benefit, including a patient with an estrogen receptor-negative disease. Conversely, none of the 3 patients with androgen receptor-negative tumors had a tumor response. Antiandrogen-based therapy showed efficacy in metastatic male breast cancer patients. Our results encourage considering antiandrogens in the therapeutic continuum, especially if supported by androgen receptor expression.

• Authors: Luigi Di Lauro, Patrizia Vici, Maddalena Barba, Laura Pizzuti, Domenico Sergi, Massimo Rinaldi, Anna Di Benedetto, Isabella Sperduti, Abeer M Shaaban, Valerie Speirs, Marcella Mottolese, Ruggero De Maria, Marcello Maugeri-Saccà
• Journal: Breast cancer research and treatment (Breast Cancer Res Treat) Vol. 148 Issue 1 Pg. 73-80 (Nov 2014) ISSN: 1573-7217 [Electronic] Netherlands
• PMID: 25238881 (Publication Type: Journal Article)

Chemical References

• AR protein, human
• Androgen Antagonists
• Antineoplastic Agents, Hormonal
• Receptors, Androgen
• Cyproterone Acetate

Topics

• Adult
• Aged
• Androgen Antagonists (therapeutic use)
• Antineoplastic Agents, Hormonal (therapeutic use)
• Breast Neoplasms, Male (drug therapy, mortality)
• Cyproterone Acetate (therapeutic use)
• Disease-Free Survival
• Humans
• Kaplan-Meier Estimate
• Male
• Middle Aged
• Receptors, Androgen (biosynthesis)
• Retrospective Studies
• Treatment Outcome