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

Publication

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

Journal Paper/Review - Jun 5, 2012

Schoenewolf Nicola L, von Moos Roger, Schraml Peter, Gillessen Sommer Silke, Ochsenbein Adrian, Simcock Mathew, Moch Holger, Mihic-Probst Daniela, Dummer Reinhard, Swiss Group for Clinical Cancer Research (SAKK)

Citation

Schoenewolf N, von Moos R, Schraml P, Gillessen Sommer S, Ochsenbein A, Simcock M, Moch H, Mihic-Probst D, Dummer R, Swiss Group for Clinical Cancer Research (SAKK). Detecting BRAF Mutations in Formalin-Fixed Melanoma: Experiences with Two State-of-the-Art Techniques. Case Rep Oncol 2012; 5:280-9.

Type

Journal Paper/Review (English)

Journal

Case Rep Oncol 2012; 5

Publication Date

Jun 5, 2012

Issn Electronic

1662-6575

Pages

280-9

Brief description/objective

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.