The effects of paclitaxel, dose density, and trastuzumab on treatment‐related amenorrhea in premenopausal women with breast cancer

BACKGROUND: Little information is available regarding the effects of new adjuvant treatment regimens on menstrual functioning in premenopausal women with early breast cancer. METHODS: The authors conducted a retrospective review of data from premenopausal women who received treatment for early breast cancer to evaluate the rates of amenorrhea in follow-up. The women who were included received treatment with either doxorubicin and cyclophosphamide (AC) or combined AC and paclitaxel (T) (AC-T) given either every 3 weeks, or as a dose-dense (DD) regimen, or as AC followed by weekly T with trastuzumab or followed by trastuzumab (AC-T+trastuzumab). A multivariate logistic regression analysis was conducted to evaluate amenorrhea during follow-up. RESULTS: Of 431 patients who were eligible for analysis, the average age at diagnosis was 13 years (range, 25-55 years), 61% of women received AC only, and 39% received AC-T. Of the 39% who received AC-T, 49% of women received DD therapy, 14% received AC-T+trastuzumab, and 71% of all patients received tamoxifen (TAM). The median follow-up was 33 months (range, 6-114 months). After adjusting for age, weight, gravidity, parity, age at menarche, smoking, alcohol use, TAM use, type and regimen of chemotherapy, and use of trastuzumab, the likelihood of remaining amenorrheic was not statistically different in patients who received AC-T versus AC (odds ratio OR, 1.59; 95% confidence interval CI, 0.8-3.2), DD treatment versus treatment every 3 weeks (OR, 0.56; 95% CI, 0.25-1.3), or AC-T + trastuzumab (OR, 0.6; 95% CI, 0.22-1.61). Amenorrhea was associated significantly with TAM use and age at diagnosis. CONCLUSIONS: Recent advances in the adjuvant treatment of early breast cancer do not appear to have increased the risk of amenorrhea in premenopausal women.