Molecular diagnostics are increasingly performed routinely in the diagnosis and management of patients with melanoma due to the development of novel therapies that target specific genetic mutations.,The development of next-generation sequencing (NGS) technologies has enabled to sequence multiple cancer-driving genes in a single assay, with improved sensitivity in mutation detection.,The main objective of this study was the design and implementation of a melanoma-specific sequencing panel, and the identification of the spectrum of somatic mutations in a series of primary melanoma samples.,A custom panel was designed to cover the coding regions of 35 melanoma-related genes.,Panel average coverage was 2,575.5 reads per amplicon, with 92,8% of targeted bases covered ≥500×.,Deep coverage enabled sensitive discovery of mutations in as low as 0.5% mutant allele frequency.,Eighty-five percent (85/100) of the melanomas had at least one somatic mutation.,The most prevalent mutated genes were BRAF (50%;50/199), NRAS (15%;15/100), PREX2 (14%;14/100), GRIN2A (13%;13/100), and ERBB4 (12%;12/100).,Turn-around-time and costs for NGS-based analysis was reduced in comparison to conventional molecular approaches.,The results of this study demonstrate the cost-effectiveness and feasibility of a custom-designed targeted NGS panel, and suggest the implementation of targeted NGS into daily routine practice.
Vemurafenib is approved for the treatment of metastatic melanoma in patients with BRAF V600 mutation.,In pivotal clinical trials, BRAF testing has always been done with the approved cobas 4800 BRAF test.,In routine practice, several methods are available and are used according to the laboratories usual procedures.,A national, multicenter, non-interventional study was conducted with prospective and consecutive collection of tumor samples.,A parallel evaluation was performed in routine practice between the cobas 4800 BRAF V600 mutation test and home brew methods (HBMs) of 12 national laboratories, labelled and funded by the French National Cancer Institute (INCa).,For 420 melanoma samples tested, the cobas method versus HBM showed a high concordance (93.3%; kappa = 0.86) in BRAF V600 genotyping with similar mutation rates (34.0% versus 35.7%, respectively).,Overall, 97.4% and 98.6% of samples gave valid results using the cobas and HBM, respectively.,Of the 185 samples strictly fulfilling the cobas guidelines, the concordance rate was even higher (95.7%; kappa = 0.91; 95%CI [0.85; 0.97]).,Out of the 420 samples tested, 28 (6.7%) showed discordance between HBM and cobas.,This prospective study shows a high concordance rate between the cobas 4800 BRAF V600 test and home brew methods in the routine detection of BRAF V600E mutations.