Validation of the VE1 immunostain for the BRAF V600E mutation in melanoma. (4th July 2014)

• Record Type: Journal Article
• Authors: Pearlstein, Michelle V.; Zedek, Daniel C.; Ollila, David W.; Treece, Amanda; Gulley, Margaret L.; Groben, Pamela A.; Thomas, Nancy E.
• Is Part Of: Journal of cutaneous pathology. Volume 41:Number 9(2014:Oct.)
• Page Start: 724
• Page End: 732
• Publication Date: 2014-07-04
• Subjects: Skin -- Diseases -- Periodicals; Dermatology -- Periodicals; 616
• DOI: 10.1111/cup.12364
• Languages: English
• ISSNs: 0303-6987

Abstract

<abstract abstract-type="main" id="cup12364-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="cup12364-sec-0001" sec-type="section"> <title>Background</title> <p id="cup12364-para-0001"> <italic>BRAF</italic> mutation status, and therefore eligibility for BRAF inhibitors, is currently determined by sequencing methods. We assessed the validity of VE1, a monoclonal antibody against the <italic>BRAF</italic> V600E mutant protein, in the detection of mutant BRAF V600E melanomas as classified by DNA pyrosequencing.</p> </sec> <sec id="cup12364-sec-0002" sec-type="section"> <title>Methods</title> <p id="cup12364-para-0002">The cases were 76 metastatic melanoma patients with only one known primary melanoma who had had <italic>BRAF</italic> codon 600 pyrosequencing of either their primary (n = 19), metastatic (n = 57) melanoma, or both (n = 17). All melanomas (n = 93) were immunostained with the BRAF VE1 antibody using a red detection system. The staining intensity of these specimens was scored from 0 to 3+ by a dermatopathologist. Scores of 0 and 1+ were considered as negative staining while scores of 2+ and 3+ were considered positive.</p> </sec> <sec id="cup12364-sec-0003" sec-type="section"> <title>Results</title> <p id="cup12364-para-0003">The VE1 antibody showed a sensitivity of 85% and a specificity of 100% as compared to DNA pyrosequencing results. There was 100% concordance between VE1 immunostaining of primary and metastatic melanomas from the same patient. V600K, V600Q, and V600R <italic>BRAF</italic> melanomas did not positively stain with VE1.</p> </sec> <sec id="cup12364-sec-0004" sec-type="section"> <title>Conclusions</title> <p id="cup12364-para-0004">This hospital‐based study finds high sensitivity and specificity for the BRAF VE1 immunostain in comparison to pyrosequencing in detection of <italic>BRAF</italic> V600E in melanomas.</p> </sec> </abstract>