A cornerstone of treatment for advanced prostate cancer is androgen deprivation therapy (ADT). In contrast to this androgen antagonism treatment in prostate cancer, androgen agonism treatment is promising in some types of cancer. The most clinically advanced iteration of this idea is found in estrogen-positive breast cancer. It has been found that the androgen receptor (AR) functions as a tumor suppressor in estrogen receptor-positive (ER+) breast cancer.1