title: Clinicopathological features in bilateral breast cancer.
abstract: OBJECTIVE
  The frequency of bilateral breast cancer is 1.4-11.0% among all breast cancers. It can present as synchronous (SC) or metachronous (MC). Data regarding clinical course of bilateral breast cancer are scarce. In this study, we therefore evaluated demographic, pathological and clinical characteristics, treatments and responses in bilateral breast cancer cases; making distinctions between metachronous-synchronous and comparing with historic one-sided data for the same parameters.
  
  
  METHODS
  One hundred fifty bilateral breast cancer cases from ten different centers between 2000 and 2011 were retrospectively scanned. Age of the cases, family history, menopausal status, pathological features, pathological stages, neoadjuvant, surgery, adjuvant and palliative chemotherapy/radiotherapy were examined in the context of the first and second occurrence and discussed with reference to the literature.
  
  
  RESULTS
  Metachronous and synchronous groups showed similar age, menopausal status, tumor type, HER2/neu expression; the family history tumor grade, tumor stage, ER-negativity rate, local and distant metastases rates, surgery, adjuvant chemotherapy application rates were identified as significantly different. Palliative chemotherapy response rate was greater in the metachronous group but median PFS rates did not differ between the groups.
  
  
  CONCLUSIONS
  Although bilateral breast cancer is not frequent, MC breast cancer is different from SC breast cancer by having more advanced grade, stage, less ER expression, more frequent rates of local relapse and distant metastasis and better response to chemotherapy in case of relapse/metastasis.
authors.affiliation: Department of Medical Oncology, Gazi University Medical Faculty, Ankara, Turkey. meltembaykara@yahoo
authors.forename: Meltem
authors.initials: M
authors.lastname: Baykara
authors.forename: Selcuk Cemil
authors.initials: SC
authors.lastname: Ozturk
authors.forename: Suleyman
authors.initials: S
authors.lastname: Buyukberber
authors.forename: Kaan
authors.initials: K
authors.lastname: Helvaci
authors.forename: Nuriye
authors.initials: N
authors.lastname: Ozdemir
authors.forename: Necati
authors.initials: N
authors.lastname: Alkis
authors.forename: Veli
authors.initials: V
authors.lastname: Berk
authors.forename: Dogan
authors.initials: D
authors.lastname: Koca
authors.forename: Ugur
authors.initials: U
authors.lastname: Coskun
authors.forename: Berna
authors.initials: B
authors.lastname: Oksuzoglu
authors.forename: Dogan
authors.initials: D
authors.lastname: Uncu
authors.forename: Erkan
authors.initials: E
authors.lastname: Arpaci
authors.forename: Basak Oven
authors.initials: BO
authors.lastname: Ustaalioglu
authors.forename: Umut
authors.initials: U
authors.lastname: Demirci
authors.forename: Mehmet
authors.initials: M
authors.lastname: Kucukoner
authors.forename: Gamze Gokoz
authors.initials: GG
authors.lastname: Dogu
authors.forename: Suleyman
authors.initials: S
authors.lastname: Alici
authors.forename: Tulay
authors.initials: T
authors.lastname: Akman
authors.forename: Metin
authors.initials: M
authors.lastname: Ozkan
authors.forename: Ulku Yalcintas
authors.initials: UY
authors.lastname: Aslan
authors.forename: Ayse Gok
authors.initials: AG
authors.lastname: Durnali
authors.forename: Mustafa
authors.initials: M
authors.lastname: Benekli
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology* / Q000628:therapy*; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000556:secondary / Q000628:therapy; D018275:Carcinoma, Lobular / Q000235:genetics / Q000556:secondary / Q000628:therapy; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D009367:Neoplasm Staging; D009378:Neoplasms, Multiple Primary / Q000235:genetics / Q000473:pathology* / Q000628:therapy*; D016609:Neoplasms, Second Primary / Q000235:genetics / Q000473:pathology* / Q000628:therapy*; D010166:Palliative Care; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D012189:Retrospective Studies
chemical_list: D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; C508053:ERBB2 protein, human