Amenorrhea in premenopausal women after adjuvant chemotherapy for breast cancer

Chemotherapy and ovarian ablation both independently improve survival in premenopausal women with hormone-sensitive breast cancer. Amenorrhea is a well-recognized occurrence after chemotherapy. The rate of chemotherapy-induced amenorrhea varies with patient age and chemotherapy regimens administered. However, the impact of chemotherapy-induced amenorrhea on prognosis is still being defined. Older studies in premenopausal women argue that the benefit with chemotherapy is a result of direct cytotoxicity alone. However, studies that restrict outcome analysis to hormone receptor-positive tumors suggest that chemotherapy has a dual mechanism in women with hormone-responsive tumors; indirect endocrine manipulation secondary to chemotherapy-induced ovarian suppression and direct cytotoxicity. The significant health ramifications involved with the induction of premature menopause as well as potential benefits necessitate a comprehensive evaluation of chemotherapy-induced amenorrhea. This review will discuss the incidence of amenorrhea with commonly-used adjuvant chemotherapeutic regimens, the possible benefits of chemotherapy-induced amenorrhea, and the challenges of interpreting the existing data in breast cancer trials.