title: Prognostic value of multiple reverse transcription-PCR tyrosinase testing for circulating neoplastic cells in malignant melanoma.
abstract: BACKGROUND
  The reverse transcription-PCR tyrosinase assay (TYR test) cannot reliably detect malignant melanoma (MM) cells in blood as the cells often circulate at low concentrations. We evaluated the prognostic value of multiple TYR testing, the prognostic significance of individual positive TYR test results (TYR+) in asymptomatic melanoma patients, and whether statistical analysis could help in the interpretation of results of a test that measures phenomena that typically occur below its detection threshold.
  
  
  METHODS
  MM patients in stages I-IV (n = 150) underwent multiple testing with the TYR test during the course of their disease. TYR testing was performed as described by Smith et al. (Lancet 1991;38:1227-9). Statistical analyses were performed with the logistic function and t-test procedures.
  
  
  RESULTS
  The relationship between MM stage and the frequency of TYR+ was statistically significant (P = 0.011). Higher frequency of TYR+ in clinically asymptomatic patients after complete resection of the primary tumor was associated with an increased risk of recurrence of MM (prognostic sensitivity, 62%; specificity, 78%).
  
  
  CONCLUSIONS
  A single positive TYR test provides a warning for disease relapse, suggesting that multiple TYR testing might provide more reliable predictions of disease progression. Multiple testing and statistical analysis using a logistic function might allow for the interpretation of apparently inconsistent results of tests for very rare cells.
authors.affiliation: Department of Oncology, Military Institute of Medicine, Szaserów 128 Street, 00-909 Warsaw, Poland. jolaszen@wim.mil.pl
authors.forename: Jolanta
authors.initials: J
authors.lastname: Szenajch
authors.forename: Bogdan
authors.initials: B
authors.lastname: Jasiński
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Synowiec
authors.forename: Jadwiga
authors.initials: J
authors.lastname: Kulik
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Chomicka
authors.forename: Jerzy
authors.initials: J
authors.lastname: Struzyna
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Nowecki
authors.forename: Piotr
authors.initials: P
authors.lastname: Rutkowski
authors.forename: Włodzimierz
authors.initials: W
authors.lastname: Ruka
authors.forename: Witold
authors.initials: W
authors.lastname: Kupść
authors.forename: Janusz A
authors.initials: JA
authors.lastname: Siedlecki
authors.forename: Wiesław
authors.initials: W
authors.lastname: Wiktor-Jedrzejczak
mesh_terms: D000328:Adult; D000368:Aged; D002460:Cell Line; D005134:Eye Neoplasms / Q000097:blood / Q000175:diagnosis / Q000473:pathology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008545:Melanoma / Q000097:blood / Q000175:diagnosis* / Q000473:pathology; D008875:Middle Aged; D014442:Monophenol Monooxygenase / Q000097:blood* / Q000235:genetics; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating; D011379:Prognosis; D012044:Regression Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012878:Skin Neoplasms / Q000097:blood / Q000175:diagnosis / Q000473:pathology
chemical_list: D014442:Monophenol Monooxygenase