title: S-100 protein in peripheral blood: a marker for melanoma metastases: a prospective 2-center study of 570 patients with melanoma.
abstract: BACKGROUND
  S-100 protein, commonly used in the immunohistochemical diagnosis of malignant melanoma and melanoma metastases, has recently been introduced as a tumor marker in peripheral blood.
  
  
  OBJECTIVE
  This prospective, observational, 2-center study evaluates S-100 in peripheral blood of patients with melanoma as a marker for metastasis.
  
  
  METHODS
  With application of an immunoluminometric assay, S-100 levels in 1396 samples of 570 patients with melanoma and 53 control subjects were measured in a blinded manner.
  
  
  RESULTS
  The cut-off level for patients with melanoma without medical history of metastases versus patients with newly occurring lymph node, visceral, and/or brain metastases was 0.114 microg/L, with a sensitivity of 94% (95% confidence interval, 86.4%-98.5%) and a specificity of 91% (95% confidence interval, 87.7%-93.6%). False-negative results included patients with unknown primary melanoma and those with amelanotic melanoma metastases.
  
  
  CONCLUSIONS
  The data suggest that S-100 in the peripheral blood of patients with melanoma could serve as a marker indicating new melanoma metastases and could help to monitor the course of the disease.
authors.affiliation: Departments of Dermatology and Biometry and Medical Documentation, University of Ulm.
authors.forename: P
authors.initials: P
authors.lastname: Kaskel
authors.forename: C
authors.initials: C
authors.lastname: Berking
authors.forename: S
authors.initials: S
authors.lastname: Sander
authors.forename: M
authors.initials: M
authors.lastname: Volkenandt
authors.forename: R U
authors.initials: RU
authors.lastname: Peter
authors.forename: G
authors.initials: G
authors.lastname: Krähn
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D001932:Brain Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000556:secondary; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008545:Melanoma / Q000175:diagnosis* / Q000473:pathology / Q000556:secondary*; D008875:Middle Aged; D009367:Neoplasm Staging; D011446:Prospective Studies; D012372:ROC Curve; D009418:S100 Proteins / Q000097:blood*; D012680:Sensitivity and Specificity; D012878:Skin Neoplasms / Q000097:blood / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor; D009418:S100 Proteins