title: Magnetic resonance imaging characteristics of invasive breast cancer in women aged less than 35 years.
abstract: BACKGROUND
  With regard to clinicopathological findings and disease prognosis, breast cancer in young women is different from that in older women. However, few studies have investigated magnetic resonance imaging (MRI) characteristics of young age-onset breast cancer.
  
  
  OBJECTIVE
  To retrospectively evaluate and compare the MR images and clinicopathological characteristics of invasive breast cancer in young women (aged <35 years) with those of breast cancers in older premenopausal women (35-45 years).
  
  
  METHODS
  A total of 270 invasive breast cancers in 266 premenopausal women aged 45 years and younger who underwent preoperative breast MRI and curative surgery were identified between 2009 and 2013. The subjects were divided into a young group (< 35 years, n = 56) and an older group (35-45 years, n = 214). MRI features and clinicopathological data were compared between the two groups.
  
  
  RESULTS
  The young group had more positive axillary lymph nodes, higher histologic grade, negative estrogen receptor (ER), negative progesterone receptor (PR), and higher p53 and Ki-67 expression compared to the older group. Using MRI, the young group was more likely to display a round/oval or lobular mass shape, a smooth mass margin, and a high signal intensity on T2-weighted images when compared to the older group. In multivariate analysis, positive axillary nodal status (adjusted odds ratio [OR], 4.070; P = 0.002), higher expression of p53 (adjusted OR, 2.902; P = 0.038), lobular mass shape (adjusted OR, 4.979; P = 0.028), and smooth mass margin (adjusted OR, 5.123; P = 0.048) were independently associated with the young group.
  
  
  CONCLUSIONS
  MR morphologic features, including lobular mass shape and smooth mass margin, were independently associated with breast cancer in young women, in addition to positive axillary nodal status and higher p53 expression status.
authors.affiliation: Department of Radiology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan, Republic of Korea.
authors.forename: Jin You
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Department of Radiology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan, Republic of Korea.
authors.forename: Suck Hong
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Radiology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan, Republic of Korea youdosa@naver.com.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Department of Radiology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Busan, Republic of Korea.
authors.forename: Suk
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Radiology, Pusan National University Yangsan Hospital, Yangsan, Republic of Korea.
authors.forename: Ki Seok
authors.initials: KS
authors.lastname: Choo
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D001365:Axilla; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000473:pathology*; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000706:statistics & numerical data*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D015995:Prevalence; D056910:Republic of Korea / Q000453:epidemiology; D012307:Risk Factors; D016387:Women's Health / Q000706:statistics & numerical data; D055815:Young Adult
keywords: Breast; early-onset; magnetic resonance imaging (MRI); neoplasm – primary