2008•Applied immunohistochemistry & molecular morphologyRequires access
HER-2/neu Expression in Salivary Duct Carcinoma: An Immunohistochemical and Chromogenic In Situ Hybridization Study
Christopher Jay Johnson, Michelle B. Barry, Mohammad A. Vasef, Barry R. DeYoung
Open publisher page 63 citations
Abstract
Salivary duct carcinoma (SDC) shares significant morphologic and immunophenotypic overlap with ductal carcinoma of the breast, including HER-2/neu expression. Previous studies have detected HER-2/neu at the protein level in SDCs; however, no study, to date, has assayed whether this expression is related to gene amplification detected by chromogenic in situ hybridization (CISH). Formalin-fixed, paraffin-embedded tissue sections from 12 previously diagnosed SDCs were evaluated by immunohistochemistry (IHC) and CISH for HER-2/neu status. Result concordance was seen in all 12 cases. A total of 4 SDCs were positive by IHC; all 4 cases showed amplification with CISH. The remaining 8 cases were negative by IHC and showed no gene amplification with CISH. SDCs in this study show HER-2/neu overexpression on both the protein and gene levels in approximately 30% of cases. These findings suggest a role may exist for Herceptin (trastuzumab) based therapy in some SDC patients.