Pancreatic endocrine tumors-c-erb B2 (Her-2/neu), bcl-2, and p-53 immunohistochemical testing and their value in assessing prognosis

• Published in: Applied immunohistochemistry & molecular morphology Vol. 16; no. 1; p. 44
• Main Authors: Proca, Daniela M, Frankel, Wendy L
• Format: Journal Article
• Language: English
• Published: United States 01.01.2008
• Subjects: Humans; Pancreas - chemistry; Pancreas - cytology; Pancreatic Neoplasms - chemistry; Prognosis; Proto-Oncogene Proteins c-bcl-2 - analysis; Receptor, ErbB-2 - analysis; Tumor Suppressor Protein p53 - analysis
• ISSN: 1541-2016; 1533-4058
• DOI: 10.1097/PAI.0b013e31802e2f08

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. 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). 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. 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.