title: Pancreatic endocrine tumors-c-erb B2 (Her-2/neu), bcl-2, and p-53 immunohistochemical testing and their value in assessing prognosis.
abstract: BACKGROUND
  In an attempt to identify better prognostic factors, and the genetic basis of pancreatic endocrine tumors (PETs), we evaluated immunohistochemical reactivity for c-erb B2 (Her-2/neu), bcl-2, and p53.
  
  
  METHODS
  Two pathologists reviewed hematoxylin and eosin slides and immunohistochemical stains from 28 cases, 27 tumors and 1 nesidioblastosis. Using WHO criteria for malignancy (presence of local or lymphovascular invasion and/or metastases), cases were divided into malignant (20 cases) and benign or uncertain (8 cases). Nuclear staining in >1% of cells was considered positive for p53 and bcl-2, whereas membranous staining was considered positive for c-erb B2 (Her-2/neu).
  
  
  RESULTS
  All cases were nonimmunoreactive with anti-c-erb B2 (Her-2/neu), but focal granular or diffuse cytoplasmic staining was seen in occasional neoplasms. One malignant PET showed reactivity with anti-p53, whereas all others were negative. bcl-2 reactivity was identified in 15/28 cases: 9/20 malignant PETs and 6/8 others were positive.
  
  
  CONCLUSIONS
  c-erb B2 (Her-2/neu) and p53 are not useful prognostic factors in PET. c-erb B2 (Her-2/neu) staining must be carefully evaluated to avoid the misinterpretation of artifactual/background staining. bcl-2 is occasionally expressed in PET, but the significance of this finding is still to be determined.
authors: Department of Pathology, The Ohio State University, Marysville, OH 43040, USA. proca-1@medctr.osu.edu.
authors: Daniela M
authors: DM
authors: Proca
authors: Wendy L
authors: WL
authors: Frankel
mesh_terms: D006801:Humans; D010179:Pancreas / Q000737:chemistry / Q000166:cytology; D010190:Pancreatic Neoplasms / Q000737:chemistry*; D011379:Prognosis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
chemical_list: D019253:Proto-Oncogene Proteins c-bcl-2; D018719:Erb-b2 Receptor Tyrosine Kinases; D016159:Tumor Suppressor Protein p53