title: Neuroendocrine differentiation correlates with hormone receptor expression and decreased survival in patients with invasive breast carcinoma.
abstract: OBJECTIVE
  Invasive breast carcinoma (IBC) with neuroendocrine (NE) differentiation has been controversial in terms of its definition and clinical outcome. We investigated the incidence and clinical significance of NE differentiation in patients with IBC.
  
  
  RESULTS
  We performed immunohistochemistry for NE markers, chromogranin-A and synaptophysin on 1428 IBC samples using tissue microarrays and classified cases with NE differentiation into two groups, focal (1-49% tumour cells positive for any NE marker) and diffuse (≥50% tumour cells positive) groups. Fifty-nine cases (4.1%) showed NE differentiation immunohistochemically, and the majority did not show typical NE morphology. The presence of NE differentiation showed a significant association with positive oestrogen receptor (P = 0.001) and progesterone receptor (P = 0.008) status. Patients with NE differentiation showed worse overall survival (OS) and disease-free survival (DFS) than those without NE differentiation in both univariate (P < 0.001 for both) and multivariate (OS, P = 0.004; DFS, P < 0.001) analyses.
  
  
  CONCLUSIONS
  IBC with NE differentiation is a distinct subtype of mammary carcinoma with an aggressive clinical outcome.
authors.affiliation: Department of Pathology, Keimyung University School of Medicine, Daegu, Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Kwon
authors.forename: Young Kyung
authors.initials: YK
authors.lastname: Bae
authors.forename: Mi Jin
authors.initials: MJ
authors.lastname: Gu
authors.forename: Jung Eun
authors.initials: JE
authors.lastname: Choi
authors.forename: Su Hwan
authors.initials: SH
authors.lastname: Kang
authors.forename: Soo Jung
authors.initials: SJ
authors.lastname: Lee
authors.forename: Aeri
authors.initials: A
authors.lastname: Kim
authors.forename: Hye Ra
authors.initials: HR
authors.lastname: Jung
authors.forename: Sun Hee
authors.initials: SH
authors.lastname: Kang
authors.forename: Hoon Kyu
authors.initials: HK
authors.lastname: Oh
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D002454:Cell Differentiation; D053379:Chromogranin A / Q000378:metabolism; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000378:metabolism* / Q000401:mortality / Q000473:pathology*; D011379:Prognosis; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D016708:Synaptophysin / Q000378:metabolism; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C506150:CHGA protein, human; D053379:Chromogranin A; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C569014:SYP protein, human; D016708:Synaptophysin
keywords: breast neoplasms; neuroendocrine differentiation; prognosis