Factors-associated with short-term effect and long-term survival of ovarian function suppression in estrogen receptor positive breast cancer: a retrospective analysis

Background and purpose: Endocrine therapy has been one of the routine means of adjuvant therapy for patients with hormone receptor positive after surgery. This study aimed to analyze the factors influencing short-term effect (estrogen suppression effect) and long-term survival (disease-free survival, DFS) in patients with operable breast cancer after ovarian function suppression (OFS) therapy. Methods: DFS data and clinicopathological parameters for 435 patients with estrogen receptor (ER) positive breast cancer who underwent surgery and completed postoperative standard chemotherapy and endocrine therapy (OFS combined with tamoxifen or aromatase inhibitors) between June 2017 to June 2019 were obtained in Fudan University Shanghai Cancer Center. The authors performed univariate logistic regression and multivariate logistic regression to analyze the influencing factors of estrogen suppression, while log-rank test and COX proportional hazards regression model were used to analyze the influencing factors of disease-free survival. Results: The failure rate of estrogen suppression in patients aged ≤35 years was 8.7%, which was significantly higher than that in patients aged 35-40 years (1%, P0.05). Endocrine therapy regimen (HR = 0.49, P