title: Effects of ovarian ablation or suppression in premenopausal breast cancer: A meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  The effect of ovarian ablation or suppression (OAS) in premenopausal women with breast cancer is controversial. The overall survival (OS), disease-free survival (DFS) and adverse event of OAS versus no OAS were compared.
  
  
  METHODS
  A literature review of EMBASE, Web of Science, PUBMED, and Cochrane Library was conducted. The hazard ratio (HR) and 95% confidence interval (CI) for OS and DFS, as well as risk ratio (RR) and 95% CI for adverse events were evaluated. I-squared statistic (I2) represents heterogeneity.
  
  
  RESULTS
  Twenty-nine studies with a total of 21,249 women were included. In premenopausal women aged 40 years or younger, there were significant differences in OS (HR 0.78, 95% CI: 0.66-0.94, P=0.008, I2= 0%) and DFS (HR 0.84, 95% CI: 0.73-0.97, P=0.02, I2= 0%) between OAS and no OAS. In advanced stage breast cancer, a significant difference was found in OS (HR 0.76, 95% CI: 0.60-0.96, P=0.02, I2= 0%). Patients treated with OAS had more chances to have hot flushes (RR 1.91, 95% CI: 1.62-2.26, P < 0.01, I2= 0%) and vaginal dryness (RR 1.19, 95% CI: 1.08-1.31, P=0.0003, I2= 0%). No significant difference in depression (RR 1.28, 95% CI: 0.94-1.74, P=0.12, I2= 0%).
  
  
  CONCLUSIONS
  The study shows that OAS plays a beneficial role in premenopausal women aged 40 years or younger and advanced stage breast cancer. However, OAS is associated with increase in hot flushes and vaginal dryness.
authors.affiliation: College of Nursing and Rehabilitation, North China University of Science and Technology, Tangshan 063009, Hebei, China.
authors.forename: P
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Department of Oncological Surgery, North China University of Science and Technology Affiliated Hospital, Tangshan 063000, Hebei, China. Electronic address: lichangzai1226@163.com.
authors.forename: C-Z
authors.initials: CZ
authors.lastname: Li
authors.affiliation: Department of Oncological Surgery, North China University of Science and Technology Affiliated Hospital, Tangshan 063000, Hebei, China.
authors.forename: G-M
authors.initials: GM
authors.lastname: Jiao
authors.affiliation: Department of Oncological Surgery, North China University of Science and Technology Affiliated Hospital, Tangshan 063000, Hebei, China.
authors.forename: J-J
authors.initials: JJ
authors.lastname: Zhang
authors.affiliation: Department of Community Health, Tangshan Gongren Hospital, Tangshan 063000, Hebei, China.
authors.forename: H-P
authors.initials: HP
authors.lastname: Zhao
authors.affiliation: Department of Oncological Surgery, North China University of Science and Technology Affiliated Hospital, Tangshan 063000, Hebei, China.
authors.forename: F
authors.initials: F
authors.lastname: Yan
authors.affiliation: Department of Oncological Surgery, North China University of Science and Technology Affiliated Hospital, Tangshan 063000, Hebei, China.
authors.forename: S-F
authors.initials: SF
authors.lastname: Jia
authors.affiliation: Department of Oncological Surgery, North China University of Science and Technology Affiliated Hospital, Tangshan 063000, Hebei, China.
authors.forename: B-S
authors.initials: BS
authors.lastname: Hu
authors.affiliation: Department of Oncological Surgery, North China University of Science and Technology Affiliated Hospital, Tangshan 063000, Hebei, China.
authors.forename: C-T
authors.initials: CT
authors.lastname: Wu
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000473:pathology / Q000628:therapy*; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D017273:Goserelin / Q000008:administration & dosage / Q000009:adverse effects; D006801:Humans; D016729:Leuprolide / Q000008:administration & dosage / Q000009:adverse effects; D008207:Lymphatic Metastasis; D009367:Neoplasm Staging; D010052:Ovariectomy / Q000009:adverse effects; D017697:Premenopause; D016032:Randomized Controlled Trials as Topic; D015996:Survival Rate; D013629:Tamoxifen / Q000008:administration & dosage
chemical_list: D013629:Tamoxifen; D017273:Goserelin; D007987:Gonadotropin-Releasing Hormone; D016729:Leuprolide
keywords: Breast cancer; Meta-analysis; Ovarian ablation; Ovarian suppression; Premenopausal