title: HER2 testing in gastric cancer: molecular morphology and storage time-related changes in archival samples.
abstract: Seventy-two archival specimens of advanced gastric adenocarcinoma were analyzed by fluorescence in situ hybridization and immunohistochemistry for HER2 gene status. Gene amplification and concomitant protein overexpression were detected in 15.2% of cases. Intratumor topographical variability of HER2 amplification was observed, indicative of the late involvement of HER gene in gastric tumorigenesis. No significant correlations were found between HER2 status and histopathologic type, grade of differentiation, and Goseki classification of carcinomas, suggesting that HER2 gene is variably linked with the morphogenesis of gastric adenocarcinoma. A significant decrease of the incidence of HER2 amplified carcinomas in function of the duration of the storage of paraffin blocks was observed: 42-33% for tumor specimens paraffin-embedded in 2002-2001; 8.3%, 15.7%, 11.1% for the years 2000, 1999, 1998, respectively; 0% for cases embedded during 1997. According to these results, the reliability of the FISH and immunohistochemical assays decreases after prolonged storage of paraffin-embedded specimens.
authors.affiliation: Unit of Pathology, Institute for Cancer Research and Treatment, Candiolo-Torino, Italy. mrisio@mauriziano.it
authors.forename: Mauro
authors.initials: M
authors.lastname: Risio
authors.forename: Giovanni
authors.initials: G
authors.lastname: De Rosa
authors.forename: Ivana
authors.initials: I
authors.lastname: Sarotto
authors.forename: Laura
authors.initials: L
authors.lastname: Casorzo
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Capussotti
authors.forename: Bruno
authors.initials: B
authors.lastname: Torchio
authors.forename: Massimo
authors.initials: M
authors.lastname: Aglietta
authors.forename: Laura
authors.initials: L
authors.lastname: Chiecchio
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002454:Cell Differentiation; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D008297:Male; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis*; D013048:Specimen Handling; D013274:Stomach Neoplasms / Q000378:metabolism*; D013997:Time Factors
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases