title: Breast cancer in 30-year-old or younger patients: clinicopathologic characteristics and prognosis.
abstract: BACKGROUND
  The number of 30-year-old or younger patients with breast cancer is increasing. The aim was to describe the clinicopathological features and prognosis of 30-year-old or younger patients with breast cancer.
  
  
  METHODS
  We reviewed the records of 1,406 consecutive patients aged ≤50 years with first diagnosis of invasive breast cancer referred to surgery from March 2001 to March 2009. A total of 105 patients were aged ≤30 years (group I) and 1,301 were aged 31-50 years (group II).
  
  
  RESULTS
  Compared with patients of group II, patients of group I had a higher percentage of tumors classified as estrogen receptors (ER) negative (P < 0.001) and progesterone receptors (PR) negative (P = 0.043), with a Ki-67 labeling index ≥20% of the cells (P = 0.011). There was no difference between the two groups for pT and pN, histology, endocrine therapy, and chemotherapy. The 5-year survival of group I was 67.5% as compared with 75.3% for group II (P = 0.003).
  
  
  CONCLUSIONS
  Compared with patients aged between 31 and 50 years, patients aged ≤30 years have a greater chance of having an endocrine-unresponsive tumor and a significantly poor prognosis.
authors.affiliation: Affiliated Zhongshan Hospital of Dalian University, Dalian, 116001, China. lndlyyqiang@163.com.
authors.forename: Yongqiang
authors.initials: Y
authors.lastname: Yao
authors.affiliation: Affiliated Zhongshan Hospital of Dalian University, Dalian, 116001, China. lndlcmq@163.com.
authors.forename: Mingqian
authors.initials: M
authors.lastname: Cao
authors.affiliation: Affiliated Zhongshan Hospital of Dalian University, Dalian, 116001, China. lndlfh@163.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Fang
authors.affiliation: Affiliated Zhongshan Hospital of Dalian University, Dalian, 116001, China. lndlxjp@163.com.
authors.forename: JiPing
authors.initials: J
authors.lastname: Xie
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D018275:Carcinoma, Lobular / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human