The facts about testosterone's impact on the breast:
Androgens are antiproliferative, proapoptotic, and inhibit ERα activity and breast cancer (BCA) cell growth.
Androgens, including T pellet implants, have been used to treat BCA in the past with success and a recent study reports a 58.5% response rate in hormone-resistant metastatic breast cancer.
A retrospective, observational study following women receiving T implants in addition to conventional hormone therapy found no increase in BCA in women on T therapy compared to historical control groups, suggesting that T therapy was able to reduce the estrogen/progestin therapy associated breast cancer risk.
Testosterone's impact on overall health and quality of life, immune function, glycemic control and prevention of inflammation further support T (indirect) role in cancer prevention.
T is essential for physical health, mental health and quality of life in women including breast cancer survivors.
C. Boni, M. Pagano, M. Panebianco, et al. Therapeutic activity of testosterone in metastatic breast cancer, Anticancer Res, 34 (2014), pp. 1287-1290
C. Dimitrakakis, R.A. Jones, A. Liu, C.A. Bondy, Breast cancer incidence in postmenopausal women using testosterone in addition to usual hormone therapy, Menopause, 11 (2004), pp. 531-535
R. Glaser, C. Dimitrakakis, Testosterone and breast cancer prevention, Maturitas, Volume 82, Issue 3, 2015, Pages 291-295, ISSN 0378-5122, https://doi.org/10.1016/j.maturitas.2015.06.002