The Elusive BAP1 Mutation in Pediatric Melanocytic Tumors

This study examined pediatric melanocytic lesions to explore their potential overlap with adult BAP1 inactivated melanocytic tumors (BIMT). Analyzing 82 nevi from patients aged 2-19, the study found no lesions with concurrent BAP1 loss and BRAFV600E positivity, which are characteristic of adult BIMT. The BRAFV600E mutation was present in 90% of dermal nevi but absent in Spitz and combined Spitz dermal nevi. These findings suggest that BIMT is a low-frequency tumor in the pediatric population and may develop later in life. Future research could focus on pediatric patients with familial germline mutations and BAP1 tumor predisposition syndrome.