title: 5-S-cysteinyldopa as diagnostic tumor marker for uveal malignant melanoma.
abstract: OBJECTIVE
  To evaluate the clinical significance of 5-S-cysteinyldopa (5-S-CD), a major intermediate in melanin synthesis, as a potential diagnostic tumor marker for uveal malignant melanoma.
  
  
  METHODS
  The levels of 5-S-CD in the serum were measured by high-performance liquid chromatography in 16 patients with primary uveal melanoma. The levels of 5-S-CD were also measured in both aqueous and vitreous humor in 10 patients with uveal melanoma. The serum of healthy volunteers and patients with skin diseases other than melanoma, and the intraocular fluids of patients with cataract and vitreoretinal diseases were used as controls.
  
  
  RESULTS
  Serum concentrations of 5-S-CD in patients with uveal melanoma in the absence of extraocular metastases were close to those of controls; however, serum concentrations of 5-S-CD were significantly elevated in patients with extraocular metastases of melanoma. Concentrations of 5-S-CD in the intraocular fluids, especially vitreous humor, were higher in patients with uveal melanoma than in controls.
  
  
  CONCLUSIONS
  5-S-CD in intraocular fluids may serve as a useful biochemical marker for the diagnosis of uveal melanoma. Serum 5-S-CD may contribute to the assessment of the presence and progression of extraocular metastases in patients with uveal melanoma.
authors.affiliation: Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Goto
authors.forename: M
authors.initials: M
authors.lastname: Usui
authors.forename: K
authors.initials: K
authors.lastname: Wakamatsu
authors.forename: S
authors.initials: S
authors.lastname: Ito
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001082:Aqueous Humor / Q000737:chemistry; D014408:Biomarkers, Tumor / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives* / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000175:diagnosis*; D008875:Middle Aged; D014604:Uveal Neoplasms / Q000175:diagnosis*; D014822:Vitreous Body / Q000737:chemistry
chemical_list: C092922:5-S-cysteinyl-3,4-dihydroxyphenylalanine; D014408:Biomarkers, Tumor; D004295:Dihydroxyphenylalanine