Survey of clinicians on the use of adjuvant therapy for premenopausal women with breast cancer

Purpose Considering prognostic and anatomic stages in early-stage premenopausal patients with breast cancer, clinicians decide on performing the multigene assay, adjuvant chemotherapy, or ovarian function suppression (OFS). This decision is also based on genetic information related to hormone receptor-positive and human epidermal growth factor receptor 2 negative results. We aimed to determine the tendency to use adjuvant therapy in clinical practice. Methods From April to May 2022, clinicians of the Korean Breast Cancer Society responded to a web-based survey. The survey included 62 multiple-choice questions mainly on decision-making under different pathologic conditions. Results Among 92 responding clinicians, 91.3% were breast surgeons. For 35-year-old patients (pT2N0 and Ki-67 50% profile), 96.8% of clinicians selected chemotherapy, whereas 50.7% selected chemotherapy for patients with pT1N0, Ki-67 10%, and without Oncotype Dx (ODX). Only 35.6% selected chemotherapy for 47-year-old patients with the same profiles, while 84.3% and 49.1% chose chemotherapy with ODX recurrence score 21 and 16, respectively. More clinicians selected tamoxifen (TMX) plus OFS than aromatase inhibitor (AI) plus OFS for 5 years of endocrine therapy in patients with adjuvant chemotherapy regardless of genomic and clinical risks. However, for the same patients without adjuvant chemotherapy, more clinicians selected AI plus OFS. A longer duration of additional OFS and TMX was selected in patients with high clinical and genomic risks, and the duration of OFS was relatively shorter in older patients. Conclusion The decision regarding adjuvant therapy should be made considering clinical and genomic risks and age, and clinicians should consult with patients about adverse effects and compliance.