Taxane-based regimens as a risk factor for chemotherapy-induced amenorrhea.

Objective: The objective of our study was to show the impact of different chemotherapy regimens on the incidence of amenorrhea (chemotherapy-induced amenorrhea [CIA]) in premenopausal women of various ages with breast cancer.

Methods: This is a follow-up study of 226 premenopausal women with breast cancer who had received one of three chemotherapy regimens: conventional (cyclophosphamide/methotrexate/5-fluorouracil), anthracycline based, and anthracycline-taxane based. They were evaluated for the incidence of CIA in the follow-up clinic of the Iranian Center for Breast Cancer. A statistical analysis using SPSS software was performed, and logistic regression and Cox regression model were used to determine the risk factors for CIA.

Results: Of the 226 women with a median age of 40 years (range, 26-56 y) who participated in this study, 154 (68.1%) developed CIA. In 101 (65.6%) of these women, CIA was established. CIA was present in 52.5% of the women who had been treated with conventional regimens (cyclophosphamide/methotrexate/5-fluorouracil), 66.7% of the women who had been treated with anthracycline, and 78.7% of the women who had been treated with anthracycline-taxane. Therefore, the frequency of CIA was significantly higher in the taxane-based chemotherapy group than in the other groups (P = 0.015). Although a slightly higher incidence of CIA in women with hormone-insensitive tumors (estrogen receptor negative and progesterone receptor negative) versus hormone-sensitive tumors (estrogen receptor positive and progesterone receptor positive) who had been treated with combination regimens was observed, no statistically significant difference was found (P = 0.629). Of all of the risk factors that were evaluated in the study, anthracycline-taxane-based regimens (odds ratio, 4.059; 95% CI, 1.6-9.8) and age older than 40 years (odds ratio, 3.5; 95% CI, 1.9-6.6) were the most important factors in the development of CIA.

Conclusions: The type of chemotherapy and the age of the woman at the onset of breast cancer are the most important risk factors in CIA. Taxane-based regimens induced more CIA than did other regimens.