title: Occurrence of melanin in pheochromocytoma.
abstract: Melanin or a melanin-like pigment was observed in six of 19 pheochromocytomas. The intracellular pigment was Fontana-positive, bleach-labile dark brown to black material and distinct from coincidental hemosiderin and lipochrome. Ultrastructural components of the pigmented tumors include melanosomes and premelanosomes. Two patients with pigmented tumors had associated von Hippel-Lindau syndrome, and one had neurofibromatosis. The occurrence of melanin and melanosomes in pheochromocytoma has not been previously reported in the English literature. It is probably a reflection of the neural crest origin of this neoplasm.
authors: Department of Pathology, University of Iowa Hospitals and Clinics, Iowa City.
authors: S K
authors: SK
authors: Landas
authors: C
authors: C
authors: Leigh
authors: S M
authors: SM
authors: Bonsib
authors: K
authors: K
authors: Layne
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000737:chemistry* / Q000473:pathology / Q000648:ultrastructure; D006651:Histocytochemistry; D006801:Humans; D008543:Melanins / Q000032:analysis* / Q000096:biosynthesis; D008544:Melanocytes / Q000473:pathology / Q000648:ultrastructure; D008854:Microscopy, Electron; D010673:Pheochromocytoma / Q000737:chemistry* / Q000473:pathology / Q000648:ultrastructure
chemical_list: D008543:Melanins