title: The prognostic value of age for invasive lobular breast cancer depending on estrogen receptor and progesterone receptor-defined subtypes: A NCDB analysis.
abstract: OBJECTIVE
  We aimed to assess the effect of age on survival according to estrogen receptor (ER) and progesterone receptor (PR)-defined lobular breast cancer subtype in a wide age range.
  
  
  METHODS
  43,230 invasive lobular breast cancer women without comorbidities diagnosed between 2004 and 2011 in the National Cancer Database (NCDB) were analyzed. The effects of age on overall survival (OS) among different age groups were evaluated by log-rank test and Cox proportional model.
  
  
  RESULTS
  Multivariate analysis showed that patients diagnosed at both young (< 35 years) and old (≥ 70 years) ages had worse prognosis compared with those in the middle ages. We further analyzed the interaction between age and molecular subtype for predicting OS: in ER+PR+ subtype, the HR of OS declined with age from 1.55 (95% CI, 1.08-2.22; P = 0.019) in the group younger than 35 years to 1.38 (1.02-1.86; P = 0.036) in the 35-39 group, but increased with age to 10.1 (8.49-11.94; P < 0.001) in the group older than 79. While in ER+PR- and ER-PR- subtypes, the HRs showed no statistical differences among women diagnosed before 60 (P > 0.1); and in ER-PR+ subgroup, the HRs were similar in patients younger than 70 (P > 0.1); thus, the plots of HRs in these three subtypes remained steady until the age of 60 or 70.
  
  
  CONCLUSIONS
  Our findings identified that the effect of age on OS in lobular breast cancer varied with ER/PR-defined subtypes. Personalized treatment strategies should be developed to improve outcomes of breast cancer patients with different ages and ER/PR statuses.
authors.affiliation: Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Department of Breast Surgery, Breast Tumor Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.|Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Jieqiong
authors.initials: J
authors.lastname: Liu
authors.affiliation: Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Department of Breast Surgery, Breast Tumor Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.|Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Kai
authors.initials: K
authors.lastname: Chen
authors.affiliation: Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Department of General Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.|Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Kai
authors.initials: K
authors.lastname: Mao
authors.affiliation: Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Department of Breast Surgery, Breast Tumor Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Fengxi
authors.initials: F
authors.lastname: Su
authors.affiliation: Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Department of Breast Surgery, Breast Tumor Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Lisa K
authors.initials: LK
authors.lastname: Jacobs
mesh_terms: D000328:Adult; D000367:Age Factors; D001943:Breast Neoplasms / Q000145:classification / Q000453:epidemiology* / Q000378:metabolism / Q000401:mortality; D018275:Carcinoma, Lobular / Q000145:classification / Q000453:epidemiology* / Q000378:metabolism / Q000401:mortality; D030541:Databases, Genetic; D005260:Female; D006801:Humans; D011379:Prognosis; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D016019:Survival Analysis; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D011960:Receptors, Estrogen; D011980:Receptors, Progesterone
keywords: ER/PR-defined subtypes; age; lobular breast cancer; national cancer database; prognostic value