Ovarian Function, Not Age, Predicts the Benefit from Ovarian Suppression or Ablation for Premenopausal Women with Breast Cancer

Abstract

The role of adjuvant ovarian suppression or ablation (OS/OA) in premenopausal women with hormone receptor-positive breast cancer remains controversial. The purpose of our study was to examine which patients might benefit from the addition of OS/OA to tamoxifen. We analyzed the data of 2065 premenopausal patients with hormone receptor-positive invasive ductal carcinomas who were treated at Sun Yat-Sen University Cancer Center from 2000 to 2008. The five-year disease-free survival rate (DFSR) and overall survival rate (OSR) were compared by menstrual status and treatment. Compared with patients older than forty years of age, patients younger than forty years old had significant lower DFSRs and OSRs. The addition of OS/OA to tamoxifen increased the DFSR and OSR of patients with normal menstrual cycles after chemotherapy, regardless of their age at diagnosis. Patients with normal menstrual cycles after chemotherapy are the main beneficiaries of an adjuvant OS/OA.

Fig 1. Criteria for inclusion of patients in the study.

Fig 2. Survival curves by menstrual status after chemotherapy.

Groups were divided by the age (< 40 y/o vs ≥40 y/o). (A) and (B): DFS and OS for all population; (C) and (D), DFS and OS for patients with normal menses; (E) and (F), DFS and OS for patients with amenorrhoea.

Fig 3. Survival curves by endocrine therapy (tamoxifen vs. tamoxifen + OS/OA).

(A) and (B), DFS and OS of patients < 40 y/o + normal menses; (C) and (D), DFS and OS of patients < 40 y/o + amenorrhoea; (E) and (F), DFS and OS of patients ≥ 40 y/o + normal menses; G and H, DFS and OS of patients ≥ 40 y/o + amenorrhoea.