title: Generalized melanosis in metastatic malignant melanoma: the possible role of DOPAquinone metabolites.
abstract: Generalized melanosis occurs very rarely as a complication of malignant melanoma, and the pathogenesis of this condition is still unclear. Histological examination of pigmented skin and measurements of the DOPAquinone metabolites 5-S-cysteinyldopa (5-S-CD) and 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5MI2C) in the patient's serum and urine were carried out. Histological examination revealed basal hyperpigmentation, discrete melanoma cells and melanophages around the blood vessels and an unusual melanin deposition within collagen bundles in the dermis. The levels of 5-S-CD and 6H5MI2C were dramatically increased both in the patient's serum and urine. The deposition of DOPAquinone metabolites secreted by the melanoma cells may contribute to the unusual melanin deposition within collagen bundles in the affected dermis.
authors.affiliation: Department of Dermatology, Yamanashi Medical University, Yamanashi, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tsukamoto
authors.forename: M
authors.initials: M
authors.lastname: Furue
authors.forename: Y
authors.initials: Y
authors.lastname: Sato
authors.forename: O
authors.initials: O
authors.lastname: Takayama
authors.forename: R
authors.initials: R
authors.lastname: Akasu
authors.forename: N
authors.initials: N
authors.lastname: Ohtake
authors.forename: K
authors.initials: K
authors.lastname: Wakamatsu
authors.forename: S
authors.initials: S
authors.lastname: Ito
authors.forename: K
authors.initials: K
authors.lastname: Tamaki
authors.forename: S
authors.initials: S
authors.lastname: Shimada
mesh_terms: D000368:Aged; D016227:Benzoquinones / Q000032:analysis / Q000097:blood / Q000652:urine; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives / Q000032:analysis / Q000097:blood / Q000502:physiology / Q000652:urine; D017809:Fatal Outcome; D005834:Genital Neoplasms, Male / Q000150:complications* / Q000556:secondary; D006801:Humans; D008297:Male; D008545:Melanoma / Q000150:complications* / Q000556:secondary; D008548:Melanosis / Q000150:complications* / Q000473:pathology; D012867:Skin / Q000473:pathology; D012878:Skin Neoplasms / Q000150:complications* / Q000556:secondary
chemical_list: D016227:Benzoquinones; D004295:Dihydroxyphenylalanine; C035157:dopaquinone