The BRAF c.1799T>Ap.V600E mutation was detected in both the brain and skin tumor cells but not in the blood or normal skin cells, suggesting somatic mosaicsism for the mutation.
Mutant allele-specific imbalance of the p.V600E mutation was predominantly present in specimens with distant organ metastases (79% versus 27% in LN metastases versus 13% in primary cutaneous tumors or adjacent soft tissue, P < .001). p.V600K was detected in 23% of men older than 60 years old, compared with 6% in women older than 60 years old and 2% in both men and women younger than 60 years old (P < .001).