BRAF/NRAS Prevalence Useful for Melanoma Management
(ChemotherapyAdvisor) – The prevalence of BRAF/NRAS/p16CDKN2A mutations in paired tumor lesions from patients with melanoma is useful in the management of this disease, according to a team of Italian researchers. This conclusion is based on a study entitled “BRAF/NRAS Mutation Frequencies among Primary Tumors and Metastases in Patients with Melanoma,” which was published in the July 10 issue of the Journal of Clinical Oncology.
In the study, the investigators aimed to determine the prevalence and distribution of mutations in BRAF, NRAS, and p16CDKN2A in different melanoma tissues. To meet this aim, the investigators screened 291 tumor tissues from 132 patients with melanoma were screened by mutation analysis (automated DNA sequencing).
The investigators reported the following results. BRAF/NRAS mutations were identified in 58% of primary melanomas (43% BRAF; 15% NRAS); 62% in lymph nodes, 61% subcutaneous, 56% visceral, and 70% in brain sites. Mutations were observed in 63% of metastases (48% BRAF; 15% NRAS), a nonsignificant increase in mutation frequency after progression from primary melanoma. Of the paired samples, lymph nodes (93% consistency) and visceral metastases (96% consistency) presented a highly similar distribution of BRAF/NRAS mutations vs primary melanomas, with a significantly less consistent pattern in brain (80%) and skin metastases (75%). p16CDKN2A mutations were identified in 7% and 14% of primary melanomas and metastases.
The investigators concluded: “Our findings about the prevalence of BRAF/NRAS/p16CDKN2A mutations in paired tumor lesions from patients with melanoma may be useful in the management of this disease.”