title: Clinicopathologic features and molecular subtypes of breast cancer in young women (age ≤35).
abstract: BACKGROUND
  Breast cancer in young women is a relatively rare disease; however it tends to be more aggressive and is the leading cause of cancer death in this population. The aim of this study is to investigate the clinical and biological features of breast cancer arising in young Turkish breast cancer patients.
  
  
  METHODS
  Patients with breast cancer aged 35 or less (≤35 years) were selected for the study. In total 211 cases were included. Pathologic features; histologic subtypes, grade, lymphovascular invasion, axillary involvement, and stage were recorded for each.
  
  
  RESULTS
  The most common subtype was luminal B (36.5%), followed by luminal A (30.8%), triple negative (23.2%) and HER2+(9.5%) subtypes. Twelve percent of the patients had stage 4, 32.7% had stage 3, 46.4% had stage 2, and 6.2% had stage 1 disease at the time of diagnosis. Mean tumour diameter was 3.87 cm (range 0.3-13 cm). The axillary lymph nodes were positive in 74.4% of the patients, while lympho-vascular invasion was seen in 56.4%. Some 9.5% of patients had grade 1, 51.2% had grade 2, and 31.8% had grade 3 tumors.
  
  
  CONCLUSIONS
  Young women with breast cancer in Turkey are more likely to present with luminal B subtype. Tumors in young women are more likely to present with advanced disease, to be high grade and and to have more lymphovascular invasion. Further research should focus on whether we need new treatment strategies for young patients with breast carcinoma.
authors.affiliation: Department of Medical Oncology, Kayseri State Hospital of Research and Education, Kayseri, Turkey E-mail : semasezgingoksu@gmail.com.
authors.forename: Sema Sezgin
authors.initials: SS
authors.lastname: Goksu
authors.forename: Didem
authors.initials: D
authors.lastname: Tastekin
authors.forename: Deniz
authors.initials: D
authors.lastname: Arslan
authors.forename: Seyda
authors.initials: S
authors.lastname: Gunduz
authors.forename: Ali Murat
authors.initials: AM
authors.lastname: Tatli
authors.forename: Dilek
authors.initials: D
authors.lastname: Unal
authors.forename: Derya
authors.initials: D
authors.lastname: Salim
authors.forename: Tunc
authors.initials: T
authors.lastname: Guler
authors.forename: Hasan Senol
authors.initials: HS
authors.lastname: Coskun
mesh_terms: D000328:Adult; D000367:Age Factors; D001365:Axilla / Q000473:pathology; D001943:Breast Neoplasms / Q000145:classification* / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008207:Lymphatic Metastasis / Q000473:pathology*; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D014421:Turkey; D055815:Young Adult
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human