In the long-term follow-up of the Prevention of Early Menopause Study (POEMS)/SWOG Intergroup S0230 trial reported in the Journal of the National Cancer Institute, Moore et al found that the addition of goserelin (Zoladex) to cyclophosphamide-containing chemotherapy was associated with a higher incidence of pregnancy and nonsignificant improvements in disease-free and overall survival in premenopausal women with stage I to IIIA hormone receptor–negative breast cancer. The previously reported primary analysis from this trial showed that the addition of goserelin reduced the incidence of ovarian failure by 70% at 2 years.
In the trial, 257 women with operable disease aged 18 to 49 years were randomized to receive neoadjuvant or adjuvant chemotherapy including cyclophosphamide with or without the gonadotropin-releasing hormone agonist goserelin. Goserelin was started 1 week before chemotherapy and was continued to within 2 weeks before or after the final chemotherapy dose. A total of 218 patients, including 105 in the chemotherapy plus goserelin group and 113 in the chemotherapy-alone group were considered eligible and evaluable for the current analysis. Patients were stratified by age and chemotherapy regimen.
Pregnancy and Survival Outcomes
Median follow-up was 5.1 years for patients who were alive at the end of the study. The 5-year cumulative incidence of at least one pregnancy was 23.1% in the goserelin group vs 12.2% in the chemotherapy-alone group (adjusted odds ratio [OR] = 2.34, P = .03). Pregnancy was attempted by 23.8% of women in the goserelin group vs 16.8% of the chemotherapy-alone group (OR = 1.63, P = .18); pregnancy occurred in some women who did not report attempting pregnancy.
Patients in the goserelin plus chemotherapy group had nonstatistically significant improvements in disease-free survival (hazard ratio [HR] = 0.55, P = .09) and overall survival (HR = 0.45, P = .06). Five-year disease-free survival was 88.1% vs 78.6%, and 5-year overall survival was 91.7% vs 83.1%.
The investigators concluded, “In this long-term analysis of POEMS/S0230, we found continued evidence that patients randomly assigned to receive goserelin plus chemotherapy were not only more likely to avoid premature menopause, but were also more likely to become pregnant without adverse effect on disease-related outcomes.”
Disclosure: The study was supported by the National Cancer Institute, Breast Cancer Trials Australia and New Zealand, and AstraZeneca. The study authors’ full disclosures may be found at academic.oup.com.
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