[Effects of adjuvant chemotherapy of breast cancer on gonadal function]

Premenopausal breast cancer patients frequently develop amenorrhea during adjuvant chemotherapy. Despite psychic distress and severe weight loss are possible causes for secondary amenorrhea in cancer patients, it is in this case due to the gonadotoxicity of the cytostatic drugs. Alkylating agents, such as cyclophosphamide, damage ovaries directly, resulting in ovarian fibrosis, atretic follicles and decline in estrogen production. Elevated plasma levels of LH and FSH show adequate reaction of the hypothalamohypophyseal unit. There is no change in the androgen production of stromal cells as well as in the plasma levels of prolactin and adrenal androgen precursors. Ovarian damage goes along with hot flushes, loss of libido and dyspareunia. The onset of amenorrhea is age- and dose-related. Commonly the changes are irreversible. Estrogen replacement therapy promptly removes menopausal symptoms but is contra-indicated regarding the possible hormone-dependence of the tumor. In this case low dose medroxy-progesterone acetate is indicated.