Background: We investigated the factors that predict chemotherapy-induced amenorrhea (CIA) and the prognostic significance of CIA after long-term follow-up.
Methods: We reviewed data from 241 premenopausal patients with breast cancer who underwent adjuvant CMF or FAC chemotherapy after breast cancer surgery between January 1995 and December 2000.
Results: The median follow-up duration was 109.8 (range, 16.6-193.1) months. The age of CIA patients was older than non-CIA patients (median, 44 (range, 28-53) years and 36 (range, 25-49) years, respectively; P < 0.001). The addition of tamoxifen to the chemotherapy increased the incidence of CIA from 48% to 63.6% (P = 0.015). The 10-year disease-free survival (DFS) rate was higher in the CIA group compared with the non-CIA group in hormonal receptor-positive patients (78.4% vs. 67%, respectively; P = 0.022), and the 10-year overall survival (OS) rate also was higher in the CIA group compared with the non-CIA group (90.8% vs. 79.7%, respectively; P = 0.041).
Conclusions: The most important predictors of CIA are age and the addition of tamoxifen to the chemotherapy. CIA is likely to have an influence on DFS and OS in premenopausal patients with breast cancer with a positive hormone receptor, and it might be used as a surrogate marker for effective chemotherapy in these young Asian patients.