A mixed-methods study characterizing experiences of medical oncologists' use of gonadotropin-releasing hormone agonists for treatment of breast cancer.

Purpose: The use of ovarian function suppression (OFS) for the treatment of breast cancer in pre-menopausal women is low and little is known about medical oncologist' attitudes toward current guidelines pertaining to the use of OFS. This purpose of this study was to explore breast medical oncologists' perceptions and use of gonadotropin-releasing hormone agonists as OFS for treatment of early-stage breast cancer.

Methods: A quantitative survey exploring experiences with OFS was distributed to medical oncologists across the USA using mailing lists available through the American Medical Association. Survey responses were characterized using descriptive statistics.

Results: Oncologists in this study reported high likelihood of recommending OFS for pre-menopausal women at high risk for recurrence of hormone receptor-positive early-stage breast cancer. In addition to tumor size, nodal involvement, and 21-gene recurrence scores, administration of chemotherapy was a strong surrogate for risk of recurrence. Concerns about treatment toxicity and patient hesitancy were the top barriers to OFS utilization. Oncologists also reported low confidence in their ability to determine menopausal status in the setting of amenorrhea post-chemotherapy (9% reported feeling very confident with this task) and to monitor ovarian function while on OFS.

Conclusion: Oncologists reported strong agreement with established guidelines for the use of OFS in the treatment of early-stage hormone receptor-positive breast cancer. However, our findings indicate a need for guidance regarding the determination of menopausal status in the setting of amenorrhea and monitoring of ovarian function.