A Melanoma-Tailored Next-Generation Sequencing Panel Coupled with a Comprehensive Analysis to Improve Routine Melanoma Genotyping.

BACKGROUND Tumor molecular deciphering is crucial in clinical management. Pan-cancer next-generation sequencing panels have moved towards exhaustive molecular characterization. However, because of treatment resistance and the growing emergence of pharmacological targets, tumor-specific customized panels are needed to guide therapeutic strategies. OBJECTIVE The objective of this study was to present such a customized next-generation sequencing panel in melanoma. METHODS Melanoma patients with somatic molecular profiling performed as part of routine care were included. High-throughput sequencing was performed with a melanoma tailored next-generation sequencing panel of 64 genes involved in molecular classification, prognosis, theranostic, and therapeutic resistance. Single nucleotide variants and copy number variations were screened, and a comprehensive molecular analysis identified clinically relevant alterations. RESULTS Four hundred and twenty-one melanoma cases were analyzed (before any treatment initiation for 94.8% of patients). After bioinformatic prioritization, we uncovered 561 single nucleotide variants, 164 copy number variations, and four splice-site mutations. At least one alteration was detected in 368 (87.4%) lesions, with BRAF, NRAS, CDKN2A, CCND1, and MET as the most frequently altered genes. Among patients with BRAFV600 mutated melanoma, 44.5% (77 of 173) harbored at least one concurrent alteration driving potential resistance to mitogen-activated protein kinase inhibitors. In patients with RAS hotspot mutated lesions and in patients with neither BRAFV600 nor RAS hotspot mutations, alterations constituting potential pharmacological targets were found in 56.9% (66 of 116) and 47.7% (63 of 132) of cases, respectively. CONCLUSIONS Our tailored next-generation sequencing assay coupled with a comprehensive analysis may improve therapeutic management in a significant number of patients with melanoma. Updating such a panel and implementing multi-omic approaches will further enhance patients' clinical management.