title: Molecular types and neoadjuvant chemotherapy in patients with breast cancer- while molecular shifting is more common in luminal a tumors, the pathologic complete response is most frequently observed in her-2 like tumors.
abstract: BACKGROUND
  Pathologic complete response (pCR) is one of the most important target end-points of neoadjuvant chemotherapy (NACT) in patients with breast cancer (BC). In present study, we aimed to investigate the relationship between molecular subtypes and NACT in patients with BC.
  
  
  METHODS
  Using the Akdeniz University database, 106 patients who received NACT for operable breast cancer were retrospectively identified. Prognostic factors before and after NACT were assessed. According to the molecular subtypes, molecular shifting after NACT and tumoral and nodal response to NACT were analyzed.
  
  
  RESULTS
  The distribution of subtypes was: Luminal A, 28.3% (n=30); Luminal B, 31.1% (n=33); HER2-like, 24.5% (n=26); and basal like/ triple negative (BL/TN), 16.0% (n=17). According to molecular subtypes, pCR rates in both breast and axillary were 0%, 21.4%, 36.4% and 27.3% for luminal A, luminal B, HER2-like and BL/TN, respectively (p=0.018). Molecular subtype shifting was mostly seen in luminal A type (28.6%) after the NACT. The pCR rate in breast and axillary was significantly higher in patients with HER2-like type BC.
  
  
  CONCLUSIONS
  In patients with HER-2 like type BC, NACT may be offered in early stages. Additionally, due to molecular shifting, adjuvant treatment schedule should be reviewed again, especially in the luminal A group.
authors.affiliation: Department of Medical Oncology, Akdeniz University School of Medicine, Antalya, Turkey E-mail deryakivrak@gmail.com.
authors.forename: Derya Kivrak
authors.initials: DK
authors.lastname: Salim
authors.forename: Hasan
authors.initials: H
authors.lastname: Mutlu
authors.forename: Melek Karakurt
authors.initials: MK
authors.lastname: Eryilmaz
authors.forename: Fatma Yalcin
authors.initials: FY
authors.lastname: Musri
authors.forename: Deniz
authors.initials: D
authors.lastname: Tural
authors.forename: Seyda
authors.initials: S
authors.lastname: Gunduz
authors.forename: Hasan Senol
authors.initials: HS
authors.lastname: Coskun
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001707:Biopsy, Needle; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D002681:China; D016208:Databases, Factual; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D020360:Neoadjuvant Therapy / Q000379:methods*; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone