title: Significance of placental alkaline phosphatase (PLAP) in the monitoring of patients with seminoma.
abstract: OBJECTIVE
  To investigate the significance of placental alkaline phosphatase (PLAP) as a tumour marker for seminoma.
  
  
  METHODS
  A total of 673 serum samples from 116 patients with testicular germ cell tumours (78 seminomas and 38 non-seminomas) were analysed for several markers including PLAP, total alkaline phosphatase (AL-P), alpha fetoprotein (AFP), beta human chorionic gonadotrophin (HCG-B), and lactic dehydrogenase (LDH).
  
  
  RESULTS
  Serum PLAP was increased initially in about 50% of patients with seminoma, and the mean magnitude of elevation was about five times the normal value. There was no significant correlation between PLAP and LDH or between PLAP and HCG-B. Therefore, a combination of these three markers was of value, and resulted in a positive identification rate of 82% of patients with seminoma. False-positive results for PLAP appeared in 1.6% of 673 samples investigated.
  
  
  CONCLUSIONS
  The monitoring of serum PLAP might be of value, as fluctuations in this marker provide information about disease status and prognosis.
authors.affiliation: Department of Urology, School of Medicine, Kanazawa University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Koshida
authors.forename: T
authors.initials: T
authors.lastname: Uchibayashi
authors.forename: H
authors.initials: H
authors.lastname: Yamamoto
authors.forename: K
authors.initials: K
authors.lastname: Hirano
mesh_terms: D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood*; D014408:Biomarkers, Tumor / Q000097:blood*; D006063:Chorionic Gonadotropin / Q000378:metabolism; D004796:Clinical Enzyme Tests; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D018239:Seminoma / Q000175:diagnosis*; D013736:Testicular Neoplasms / Q000175:diagnosis*; D000509:alpha-Fetoproteins / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D006063:Chorionic Gonadotropin; D000509:alpha-Fetoproteins; D007770:L-Lactate Dehydrogenase; D000469:Alkaline Phosphatase