Immunocytochemistry and fluorescence in situ hybridization in HER-2/neustatus in cell block preparations
OBJECTIVE: Recent studies have validated the use of cytologic materials todetermine HER-2/neu status. Good concordance has been shown between results obtained byimmunocytochemistry (ICC), immunohistochemistry (IHC), fluorescence in situ hybridization (FISH) oncytologic and surgical specimens. However, the utility of cytologic cell block material indetermining HER-2/neu status has not been reported and is the subject of this study. STUDY DESIGN:HER-2/neu status was determined in 25 cases of primary or metastatic breast carcinoma by IHC andFISH. All cases were formalin-fixed, paraffin-embedded (FPPE) cell block preparations. ICC wasperformed using monoclonal antibodies TAB250 (Zymed) and CB11 (Novacastra Laboratories). FISHanalysis was performed using the PathVysion HER-2 probe kit (Vysis, Inc.). Results of ICC and FISHwere compared in each case. RESULTS: Of 25 cases studied, 17 showed no protein overexpression oramplification. Five cases showed protein overexpression and amplification. The remaining 3 casesshowed 2+ staining intensity by ICC in 10, 20, and 50% of carcinoma cells, respectively, and alldemonstrated lack of amplification. CONCLUSION: Immunocytochemistry performed on FFPE cell blockmaterial is a reliable method for determining HER-2/neu status in cytologic specimens. We recommendroutine preparation of FFPE cell block material in instances of suspected primary of metastaticbreast carcinoma.
Shin,SJ Chen,B Hyjek,E Vazquez,M
Department of Pathology and Laboratory Medicine, Weill Medical College ofCornell University, New York, New York 10021, USA. sjshin@med.cornell.edu
HER-2/neu Cells Immunocytochemistry Fluorescent in Situ Hybridization
