Clinical history of congenital lipomatosis
Adipocytes arranged in sheets
Abundant clear cytoplasm with minimal variability in size and shape
Peripherally located small monomorphic nuclei
Entrapped skeletal muscle fibers may show atrophy, which should not be confused with atypia of liposarcoma
FISH: negative for MDM2 amplification
Associated with mitochondrial DNA mutations (PMID: 9309699, 31912494)