title: Luminal B subtype: a key factor for the worse prognosis of young breast cancer patients in China.
abstract: BACKGROUND
  The prognoses of young breast cancer patients are poor. The purpose of this study is to evaluate the different characteristics and prognoses among different subtypes of young breast cancer patients.
  
  
  METHODS
  The study included 1360 patients <40 years-old (y) and 3110 patients 40-50y with operable breast cancer in Shanghai Cancer Center, Fudan University. The characteristics, overall survival (OS) and disease-free survival (DFS) were compared.
  
  
  RESULTS
  The median follow-up was 54.1 months. More grade III tumors and more lymph-vascular invasions (P < 0.01) were presented in <40y group when compared with 40-50y group. More patients <40y presented with Luminal B (25.3% vs. 17.5%, P < 0.01) and triple negative (16.7% vs. 13.4%, P < 0.05) breast cancer while fewer had Luminal A tumor (48.5% vs. 59.2%, P < 0.01). Younger patients with tumors of both Luminal A and Luminal B types were at increased risk for worse DFS (P = 0.03, HR = 1.69, 95% CI = 1.05-2.72; P < 0.01, HR = 3.61, 95% CI = 2.50-5.22) when compared with the older patients. Patients <40y with Luminal B tumor had a two point five fold higher risk of death compared with older counterparts (P < 0.01, HR = 2.54, 95% CI = 1.35-4.79), however, a worse overall survival rate was not observed in the younger women with Luminal A breast cancer (P > 0.05). In multivariate analysis, Luminal B subtype was also a strong predictor of disease relapse (HR = 1.09, 95% CI = 1.01 to 1.19, P < 0.01) in younger patients with Luminal subtype tumors.
  
  
  CONCLUSIONS
  Characteristics of breast cancer suggested a more aggressive biology in Chinese patients with breast cancer diagnosed at young age. Luminal B subtype may have a negative effect on the prognosis of young patients in China which should be validated further.
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China. forever_drawer@163.com.
authors.forename: Li-Chen
authors.initials: LC
authors.lastname: Tang
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China. 369128696@qq.com.
authors.forename: Xi
authors.initials: X
authors.lastname: Jin
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China. 12211230025@fudan.edu.cn.
authors.forename: Hai-Yuan
authors.initials: HY
authors.lastname: Yang
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China. minsmiler@126.com.
authors.forename: Min
authors.initials: M
authors.lastname: He
authors.affiliation: Department of Surgery, Revlon/UCLA Breast Canter, David Geffen School of Medicine, Los Angeles, CA, USA. Hchang@mednet.ucla.edu.
authors.forename: Helena
authors.initials: H
authors.lastname: Chang
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China. dgh20031126@gmail.com.
authors.forename: Zhi-Ming
authors.initials: ZM
authors.lastname: Shao
authors.affiliation: Department of Breast Surgery, Fudan University Shanghai Cancer Center; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China. zhimingshao@yahoo.com.
authors.forename: Gen-Hong
authors.initials: GH
authors.lastname: Di
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000473:pathology* / Q000628:therapy; D002681:China; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D055815:Young Adult
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases