title: Identification of patients with hormone receptor-positive breast cancer who need adjuvant tamoxifen therapy for more than 5 years.
abstract: OBJECTIVE
  Extended hormonal therapy with tamoxifen for > 5 years has improved disease-free survival (DFS) and overall survival (OS) in hormone receptor (HR)-positive breast cancer patients. The aim of this study was to identify the HR-positive breast cancer women who need adjuvant tamoxifen for > 5 years.
  
  
  METHODS
  Between 1990 and 2004, 1104 HR-positive breast cancer patients who had received tamoxifen treatment at our institution and had been disease free for at least 6 years were included in this analysis. Univariate and multivariate analyses of prognostic factors for late recurrence were performed using the binary logistic regression model.
  
  
  RESULTS
  During a median follow-up period of 10.9 years after surgery, 70 patients died and 99 showed recurrence. In multivariate analysis, age < 40 years (p < 0.001) and lymph node metastasis (p < 0.001) were associated with higher rates of recurrence. We stratified patients into high-risk (age < 40 years or positive lymph node status, 536 patients) and low-risk (age > 40 years and negative lymph node status, 566 patients) groups. The recurrence rates were 14.6% and 3.5% in the high-risk and low-risk groups, respectively. Patients in the high-risk group had poorer disease-free survival (p < 0.001) and overall survival (p = 0.010) than those in the low-risk group.
  
  
  CONCLUSIONS
  Our findings suggest that HR-positive breast cancer women either aged < 40 years or with positive lymph node status were justified in continuing with tamoxifen therapy for > 5 years.
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Chiao-En
authors.initials: CE
authors.lastname: Wu
authors.affiliation: Division of Breast Surgery, Department of General Surgery, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Shin-Cheh
authors.initials: SC
authors.lastname: Chen
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Hsien-Kun
authors.initials: HK
authors.lastname: Chang
authors.affiliation: Division of Breast Surgery, Department of General Surgery, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Yung-Feng
authors.initials: YF
authors.lastname: Lo
authors.affiliation: Department of Pathology, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Swei
authors.initials: S
authors.lastname: Hsueh
authors.affiliation: Division of Hematology-Oncology, Department of Internal Medicine, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan, Taiwan. Electronic address: yclinof@adm.cgmh.org.tw.
authors.forename: Yung-Chang
authors.initials: YC
authors.lastname: Lin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage* / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality*; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008207:Lymphatic Metastasis; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D013624:Taiwan; D013629:Tamoxifen / Q000008:administration & dosage* / Q000627:therapeutic use
chemical_list: D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen
keywords: adjuvant therapy; breast cancer; hormonal therapy; late recurrence; tamoxifen