title: Hazard of breast cancer-specific mortality among women with estrogen receptor-positive breast cancer after five years from diagnosis: implication for extended endocrine therapy.
abstract: OBJECTIVE
  More than half of the patients with estrogen receptor (ER)-positive breast cancers will relapse and die from breast cancer at 5-10 yr after diagnosis despite 5-yr endocrine therapy. Subpopulations of ER-positive patients at high risk of breast cancer-specific mortality (BCSM) at 5-10 yr are undetermined.
  
  
  METHODS
  Using the Surveillance, Epidemiology, and End-Results program (1990-2003), we analyzed the relative hazard ratio (HR) and absolute HR of BCSM and the cumulative 10-yr breast cancer-specific survival (BCSS) in 111,993 breast cancer patients, stratified by ER, age, and lymph node (LN), and adjusted for other prognostic factors.
  
  
  RESULTS
  At 5-10 yr after diagnosis, ER-positive patients had increased risk of BCSM [HR, 0.71; 95% confidence interval (CI), 0.66-0.76; ER-positive as reference] compared with ER-negative patients. Specifically, younger ER-positive patients (<40 yr) had a constant plateau of annual hazard rate, a higher hazard of BCSM (HR, 0.43; 95% CI, 0.35-0.52; ER-positive as reference), and poor 10-yr BCSS, despite LN status. Among ER-positive patients aged 40-60 yr having no obvious plateau of hazard rate, only those with LN-positive disease had a significantly increased hazard of BCSM and poor 10-yr BCSS. Elderly ER-positive patients aged 60-74 yr had a hazard of BCSM, similar to that of ER-negative patients, and those with LN-positive disease had poor 10-yr BCSS.
  
  
  CONCLUSIONS
  Our findings help to define the ER-positive subpopulations at higher risk of BCSM at 5-10 yr after diagnosis and are useful in choosing candidates for clinical trials of extended endocrine therapy after 5-yr treatment and in guiding individualized treatment.
authors.affiliation: Department of Breast Surgery, Cancer Center and Cancer Institute, Shanghai Medical College, Fudan University, Shanghai 200032, People's Republic of China. yukd@shca.org.cn
authors.forename: Ke-Da
authors.initials: KD
authors.lastname: Yu
authors.forename: Jiong
authors.initials: J
authors.lastname: Wu
authors.forename: Zhen-Zhou
authors.initials: ZZ
authors.lastname: Shen
authors.forename: Zhi-Ming
authors.initials: ZM
authors.lastname: Shao
mesh_terms: D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000175:diagnosis / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality*; D002277:Carcinoma / Q000175:diagnosis / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D060046:Maintenance Chemotherapy / Q000379:methods; D008875:Middle Aged; D018579:Patient Selection; D011379:Prognosis; D011960:Receptors, Estrogen / Q000378:metabolism; D018426:SEER Program; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D018931:Antineoplastic Agents, Hormonal; D011960:Receptors, Estrogen