Antiandrogen therapy in metastatic male breast cancer: results from an updated analysis in an expanded case series
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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.
KeywordsMetastatic male breast cancer Antiandrogens Cyproterone acetate GnRH analogs Androgen receptor
We thank Dr Tania Merlino for language revisions and Dr Ana Maria Edlisca for editorial assistance. We are also grateful to Prof Massimo Lopez for his critical appraisal and constructive suggestions.
Conflict of interest
The authors declare that they have no conflict of interest. Data included in the present study were partly presented at the 1999 ASCO Annual Meeting (abstract 415), Atlanta, GA, May 15–18.
- 7.Zagouri F, Sergentanis TN, Koutoulidis V, Sparber C, Steger GG, Dubsky P, Zografos GC, Psaltopoulou T, Gnant M, Dimopoulos MA et al (2013) Aromatase inhibitors with or without gonadotropin-releasing hormone analogue in metastatic male breast cancer: a case series. Br J Cancer 108:2259–2263PubMedCrossRefPubMedCentralGoogle Scholar
- 11.Johansson I, Nilsson C, Berglund P, Lauss M, Ringnér M, Olsson H, Luts L, Sim E, Thorstensson S, Fjällskog ML et al (2012) Gene expression profiling of primary male breast cancers reveals two unique subgroups and identifies Nacetyltransferase-1 (NAT1) as a novel prognostic biomarker. Breast Cancer Res 14:R31PubMedCrossRefPubMedCentralGoogle Scholar
- 13.Shaaban AM, Ball GR, Brannan RA, Cserni G, Di Benedetto A, Dent J, Fulford L, Honarpisheh H, Jordan L, Jones JL et al (2012) A comparative biomarker study of 514 matched cases of male and female breast cancer reveals gender-specific biological differences. Breast Cancer Res Treat 133:949–958PubMedCrossRefGoogle Scholar