Treatment-related amenorrhea common in young breast cancer patients

Young women with breast cancer who are receiving treatment with modern chemotherapy regimens are likely to develop short episodes of treatment-related amenorrhea (TRA), but the vast majority of them will maintain or regain menstrual function, a study has found.

The study used data from the Young Women’s Breast Cancer Study (YWS) and included 789 women (median age 36 years) with stage 0–III breast cancer. Of these, 109 (13.8 percent) were at age ≤30 years at diagnosis, 216 (27.4 percent) at age 31–35 years, and 464 (58.8 percent) at age 36–40 years. Most of the women (592, 75.0 percent) received chemotherapy.

At 1 year postdiagnosis, TRA occurred in 286 (36.2 percent) women, but menses resumed for most of them. Factors associated with 1-year TRA were older age (≥30 vs 36–40 years: odds ratio [OR], 0.29, 95 percent confidence interval [CI], 0.17–0.48; 31–35 vs 36–40 years: OR, 0.67, 95 percent CI, 0.46–0.94; p=0.02), normal body mass index (BMI; ≥25 vs 18.5–24 kg/m²: OR, 0.59, 95 percent CI, 0.41–0.83; p<0.01), chemotherapy (OR, 5.55, 95 percent CI, 3_.60–8.82; p<0.01), and tamoxifen use (OR, 1.55, 95 percent CI, 1.11–2.16; p=0.01).

TRA rates were generally similar across most standard chemotherapy regimens (docetaxel/carboplatin/trastuzumab +/− pertuzumab: 55.6 percent; docetaxel/cyclophosphamide +/− trastuzumab/pertuzumab: 41.8 percent; doxorubicin/cyclophosphamide/paclitaxel +/− trastuzumab/pertuzumab: 44.1 percent), but nominally lower with doxorubicin/cyclophosphamide (25 percent) and with paclitaxel/trastuzumab (11.1 percent).

The present study may have important implications, such that lower BMI may independently predict TRA and because docetaxel/cyclophosphamide, which is associated with TRA risk, is increasingly being used in lieu of anthracycline-containing regimens.

Taken together, the findings may help inform use of fertility preservation strategies as well as the potential need for ovarian suppression following modern chemotherapy for young women with oestrogen receptor-positive breast cancer.