Oncologists´ perspectives and practice on exogenous reproductive hormone use in breast cancer patients

Abstract: Purpose: the study aimed to investigate oncologists´ perspectives and practices on their prescription of oral hormonal contraceptives (OHC), menopausal hormone therapy (MHT) and local estrogen therapy in patients with prior breast cancer diagnosis or BRCA-mutation carriers. Method: The study was a web-based survey, based on fictional patient cases that was sent out to 134 breast oncologists in Sweden. Thirty-six oncologists responded and included in the analysis. Results: Most oncologists would not recommend MHT after breast cancer diagnosis except from the case of estrogen-receptor negative disease where 38.9% would recommend. Similarly, non-hormonal contraceptives were recommended from most oncologists in different clinical scenarios. Regarding MHT in BRCA-mutations carriers, 11.1% would recommend MHT in patients without mastectomy whereas 50% would recommend MHT in patients who have undergone prophylactic mastectomy. Non-hormonal treatment followed by low-dose estriol were the most common treatment strategies for dry vagina after breast cancer diagnosis among oncologists whereas estriol-containing treatment was also a relatively common approach in patients treated with tamoxifen. Conclusion: We found unanimous practices in some clinical scenarios where there is some evidence, and more variable practice where the evidence is weak or completely absent. The presence of guidelines for some clinical scenarios seems to increase the common view among oncologists.