Self-Reported Outcomes of Endocrine Therapy with or Without Ovarian Suppression in Premenopausal Breast Cancer...

Background: Endocrine therapy (ET) with or without ovarian function suppression (OFS) is a cornerstone treatment for estrogen receptor-positive (ER+) breast cancer (BC) in premenopausal women, but its impact on quality of life (QoL) and sexual health remains a concern. Methods: We conducted a multicenter, prospective, observational study including premenopausal women (≤50 years) diagnosed with stage I-III ER+ BC and treated in private healthcare facilities in Brazil between 2013 and 2023. Patients received ET alone (ET-only) or combined with OFS (OFS-ET). QoL was assessed at baseline and 3, 6, 9, 12, and 24 months using the EORTC QLQ-BR23. Sexual functioning and sexual enjoyment were prespecified primary outcomes. Logistic regression identified factors associated with OFS use, and Fisher's exact test was applied for categorical comparisons at 24 months. Results: Among 363 patients (80% ET-only, 20% ET + OFS), younger age, advanced stage, and chemotherapy were independently associated with OFS use. Both groups reported early declines in sexual functioning and enjoyment. By 24 months, ET-only patients had returned to baseline, whereas OFS patients remained below baseline. At the item level, no significant differences were observed in sexual desire (51.5% vs. 42.0%; p = 0.33) or enjoyment (26.0% vs. 13.5%; p = 0.20). Lack of sexual activity was more frequent in the OFS group (60.6% vs. 41.2%; p = 0.05). Body image was significantly more impaired with OFS, with a higher proportion of patients reporting feeling less attractive (38.2% vs. 19.9%; p = 0.04) and less feminine (26.5% vs. 11.7%; p = 0.05). Conclusions: ET impairs sexual health in young BC survivors, particularly when combined with OFS. These findings underscore the need for routine sexual health assessments and supportive interventions in survivorship care.