STUDY QUESTION

Does goserelin, a GnRH agonist, have a protective effect in young breast cancer patients in terms of ovarian reserve markers anti-Müllerian hormone (AMH) and antral follicle count (AFC) during chemotherapy?

SUMMARY ANSWER

Compared with chemotherapy alone, concurrent goserelin is associated with a higher probability of ovarian reserve recovery at 1 year after chemotherapy.

WHAT IS KNOWN ALREADY

Previous studies on the administration of goserelin to protect ovarian function during chemotherapy have produced conflicting results because of the endpoint used, namely, chemotherapy-induced amenorrhoea. Reproductive medicine specialists consider AMH and AFC as the most sensitive ovarian reserve markers; however, they have never been used as biomarkers to assess the potential protective effects on ovarian reserve of goserelin during chemotherapy.

STUDY DESIGN, SIZE, DURATION: This was a prospective cohort study in which patients were assigned to receive (neo)adjuvant chemotherapy with goserelin (the goserelin group) or without goserelin (the control group) according to each patient's preference. Of 242 breast cancer patients enrolled between December 2015 and November 2019, 76 in control group and 73 in goserelin group were able to be assessed at 1 year after chemotherapy.

PARTICIPANTS/MATERIALS, SETTING, METHODS: Premenopausal patients with a regular menstrual cycle and aged 18-45 years were eligible for enrolment if they were newly diagnosed with stages I-III breast cancer for which treatment with adjuvant or neoadjuvant chemotherapy was planned. Each patient in the goserelin group was given a subcutaneous dose of 3.6 mg at least 1 week before the first cycle of chemotherapy and then every 4 weeks for the duration of chemotherapy. Ovarian reserve markers and menstrual status were evaluated before and after chemotherapy in the two treatment groups. The primary endpoint was the AMH recovery rate, the secondary endpoints were the recovery rates of AFC, estradiol (E2), follicle-stimulating hormone (FSH) and menstruation.

MAIN RESULTS AND THE ROLE OF CHANCE

Among 149 patients (76 in the control group and 73 in the goserelin group) with complete data at 1 year after chemotherapy, the adjusted recovery rate of AMH was 46.5% and 21.8% in the goserelin group and control group, respectively (odds ratio: 3.08; P = 0.002). The trends in AFC and FSH recovery rates were consistent with that in AMH recovery rate. Notably, AMH levels remained low in 41.3% of patients whose menstrual activity had resumed.

LIMITATIONS, REASONS FOR CAUTION: Randomisation was not performed because of ethical considerations, so selection bias was inevitable, although propensity score weighting was done. The study was also underpowered because 21.5% (52/242) of enrolled patients received GnRH agonist-containing endocrine therapy and could not be analysed at 1 and 2 years after chemotherapy.

WIDER IMPLICATIONS OF THE FINDINGS

Our results indicate that co-administration of goserelin with chemotherapy provides obvious ovarian reserve protection in these young breast cancer patients. We expect that these results will be applicable in clinical practice for young breast cancer patients.

STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the National Key R&D Program of China No. 2016YFC0901302, by the Research and Development Fund of Peking University People's Hospital No. RD2014-13, RDY2017-19 and by AstraZeneca. The authors have no disclosures.

TRIAL REGISTRATION NUMBER

NCT02430103.