title: Highly Concordant Results Between Immunohistochemistry and Molecular Testing of Mutated V600E BRAF in Primary and Metastatic Melanoma.
abstract: This study tested the sensitivity and specificity of VE1 antibody raised against BRAFV600E protein, on 189 melanoma samples, compared with molecular testing. In addition, the therapeutic response to BRAF inhibitors was analysed in 27 patients, according to staining intensity (scored from weak to strong) and pattern (homogeneous or heterogeneous). BRAFV600E status during melanoma progression was evaluated in a cohort of 54 patients with at least paired-samples. High sensitivity (98.6%) and specificity (97.7%) of VE1 were confirmed. During melanoma progression different samples showed concordant phenotypes. Heterogeneous VE1 staining was observed in 28.5% of cases, and progression-free survival was higher in patients with tumour samples displaying such staining. These findings suggest that only VE1-negative tumours would be genotyped to detect other BRAFV600 mutations, and that either primary melanoma or metastasis can be tested using immunohistochemistry, according to the material available.
authors.affiliation: Department of Pathology, Institut Universitaire du Cancer Toulouse Oncopole, 1, Avenue Irène Joliot-Curie, FR-31059 Toulouse, France.
authors.forename: Laure
authors.initials: L
authors.lastname: Manfredi
authors.forename: Nicolas
authors.initials: N
authors.lastname: Meyer
authors.forename: Emilie
authors.initials: E
authors.lastname: Tournier
authors.forename: David
authors.initials: D
authors.lastname: Grand
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Uro-Coste
authors.forename: Philippe
authors.initials: P
authors.lastname: Rochaix
authors.forename: Pierre
authors.initials: P
authors.lastname: Brousset
authors.forename: Laurence
authors.initials: L
authors.lastname: Lamant
mesh_terms: D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor / Q000032:analysis; D004252:DNA Mutational Analysis; D018450:Disease Progression; D005838:Genotype; D006801:Humans; D007150:Immunohistochemistry; D008545:Melanoma / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D009154:Mutation / Q000235:genetics*; D009362:Neoplasm Metastasis; D010641:Phenotype; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology
chemical_list: D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D048493:Proto-Oncogene Proteins B-raf