Xanthogranulomatous Epithelial Tumor in a Pediatric Patient. A Potential Diagnostic Pitfall With Non-Langerhans Cell Histiocytic Neoplasms, Particularly Juvenile Xanthogranuloma

Xanthogranulomatous epithelial tumor is a recently described neoplasm harboring recurrent HMGA2::NCOR2 fusions, which, owing to its extensive xanthogranulomatous appearance with abundant foamy histiocytes and frequent Touton-type giant cells, may be confused with other inflammatory and neoplastic entities. We present a case arising in the right arm subcutaneous tissues of a 10-year-old boy, which was initially interpreted as a non-Langerhans cell histiocytic neoplasm compatible with Juvenile xanthogranuloma.