Dataset Information

Detecting BRAF Mutations in Formalin-Fixed Melanoma: Experiences with Two State-of-the-Art Techniques.

ABSTRACT: BACKGROUND:Melanoma is characterized by a high frequency of BRAF mutations. It is unknown if the BRAF mutation status has any predictive value for therapeutic approaches such as angiogenesis inhibition. PATIENTS AND METHODS:We used 2 methods to analyze the BRAF mutation status in 52 of 62 melanoma patients. Method 1 (mutation-specific real-time PCR) specifically detects the most frequent BRAF mutations, V600E and V600K. Method 2 (denaturing gel gradient electrophoresis and direct sequencing) identifies any mutations affecting exons 11 and 15. RESULTS:Eighteen BRAF mutations and 15 wild-type mutations were identified with both methods. One tumor had a double mutation (GAA) in codon 600. Results of 3 samples were discrepant. Additional mutations (V600M, K601E) were detected using method 2. Sixteen DNA samples were analyzable with either method 1 or method 2. There was a significant association between BRAF V600E mutation and survival. CONCLUSION:Standardized tissue fixation protocols are needed to optimize BRAF mutation analysis in melanoma. For melanoma treatment decisions, the availability of a fast and reliable BRAF V600E screening method may be sufficient. If other BRAF mutations in exons 11 and 15 are found to be of predictive value, a combination of the 2 methods would be useful.

SUBMITTER: Schoenewolf NL

PROVIDER: S-EPMC3383294 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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Detecting BRAF Mutations in Formalin-Fixed Melanoma: Experiences with Two State-of-the-Art Techniques.

Schoenewolf Nicola L NL Dummer Reinhard R Mihic-Probst Daniela D Moch Holger H Simcock Mathew M Ochsenbein Adrian A Gillessen Silke S Schraml Peter P von Moos Roger R

Case reports in oncology 20120501 2

<h4>Background</h4>Melanoma is characterized by a high frequency of BRAF mutations. It is unknown if the BRAF mutation status has any predictive value for therapeutic approaches such as angiogenesis inhibition.<h4>Patients and methods</h4>We used 2 methods to analyze the BRAF mutation status in 52 of 62 melanoma patients. Method 1 (mutation-specific real-time PCR) specifically detects the most frequent BRAF mutations, V600E and V600K. Method 2 (denaturing gel gradient electrophoresis and direct ...[more]

PMID: 22740817

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Dataset Information

Detecting BRAF Mutations in Formalin-Fixed Melanoma: Experiences with Two State-of-the-Art Techniques.

Publications

Detecting BRAF Mutations in Formalin-Fixed Melanoma: Experiences with Two State-of-the-Art Techniques.

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