Next generation sequencing aids diagnosis and management in a case of encephalocraniocutaneous lipomatosis

Abstract

AbstractEncephalocraniocutaneous lipomatosis (ECCL) is a rare neurocutaneous disorder caused by somatic FGFR1 and KRAS variants. It shares significant phenotypic overlap with several closely related disorders caused by mutations in the RAS‐MAPK pathway (mosaic RASopathies). We report a diagnostically challenging case of ECCL in which next‐generation sequencing of affected tissue identified a pathologic FGFR1 p.K656E variant, thereby establishing a molecular diagnosis. Patients with FGFR1‐associated ECCL carry a risk of developing malignant brain tumors; thus, genetic testing of patients with suspected ECCL has important management implications.