Diagnostic Value of Immunohistochemistry for the Detection of the BRAFV600E Mutation in Primary Lung Adenocarcinoma Caucasian Patients
Marius Ilie, Elodie Long-Mira, Veronique Hofman, Berengere Dadone, Charles-Hugo Marquette, Jerome Mouroux, Jean-Michel Vignaud, Hugues Begueret, Jean-Philippe Merlio, David Capper, Andreas von Deimling, Jean-Francois Emile, Paul Hofman. Pasteur Hospital, Nice, France; Central Hospital, Nancy, France; Haut-Lévêque Hospital, Pessac, France; Institute for Pathology, University of Heidelberg, Heidelberg, Germany; Ambroise Paré Hospital, Boulogne, France
Background: Non-small cell lung carcinoma (NSCLC) patients with a BRAFV600E mutation benefit from targeted therapy. The usefulness of immunohistochemistry (IHC) as an alternative approach for detection of BRAFV600E in NSCLC patients has not been evaluated until now. This study compared the specificity and sensitivity of IHC with other methods for detection of BRAFV600E in primary lung adenocarcinoma.
Design: BRAF mutations were analyzed by DNA sequencing of a Caucasian subpopulation of selected 450/1509 (30%) EGFR, KRAS, PI3KA, Her2 and EML4-ALK wild-type (wt) primary lung adenocarcinomas. Detection of the BRAFV600E mutation was performed by IHC using the VE1 clone antibody and compared to results of other molecular methodologies.
Results: 40/450 (9%) of tumors harbored a BRAF mutation, which corresponded to either a BRAFV600E or a non BRAFV600E mutation in 21/450 (5%) and 19/450 (4%) cases, respectively. IHC VE1 assay was positive in 19/21 (90%) BRAFV600E mutated tumors and negative in all BRAFnonV600E mutated tumors.
Conclusions: IHC using the VE1 clone is a specific and sensitive method for the detection of BRAFV600E and may be an alternative to molecular biology for detection of mutations in NSCLC.
Monday, March 4, 2013 1:45 PM
Proffered Papers: Section D, Monday Afternoon