The<unk>  is a paradoxical improvement in breast cancer caused by discontinuation of<unk>  therapy for breast cancer. It has been documented rarely with the selective estrogen receptor modulators (SERMs) tamoxifen and raloxifene. The phenomenon indicates that these agents can somehow result in stimulation of breast cancer tumor progression under certain circumstances. One proposed theory for the mechanism is that the sensitivity of breast cells to estrogens shifts with estrogen deprivation, and upon<unk><unk> , endogenous estrogen acts in the manner of high-dose estrogen therapy in the breast to inhibit breast cancer growth and induce breast cancer cell death. The<unk><unk>  syndrome is analogous to but less common and well-known than the antiandrogen<unk>  syndrome, a phenomenon in which paradoxical improvement in prostate cancer occurs upon discontinuation of antiandrogen therapy.
Antiestrogen withdrawal response
Rapid hormone cycling
Progestin-induced virilization
Estrogen-dependent condition
Androgen-dependent condition
Anovulatory cycle
Side effects of bicalutamide
Side effects of cyproterone acetate