title: A comparison between des-gamma-carboxy prothrombin and alpha-fetoprotein as markers of hepatocellular carcinoma in southern African blacks.
abstract: Des-gamma-carboxy prothrombin (DCP), a precursor of prothrombin, has been reported recently to be as good a marker, or even better, of hepatocellular carcinoma than alpha-fetoprotein (alpha-FP). The sensitivity, specificity and predictive values of the two markers have been compared in 98 southern African Blacks with hepatocellular carcinoma and in 120 Black controls with various diseases which might be mistaken clinically for this tumour: 32 with hepatic metastases, 33 with amoebic hepatic abscesses, and 55 with chronic hepatic parenchymal disease. DCP levels were measured using a chromogenic assay with Dispholidus typus venom and staphylocoagulase. The agreement between the two methods was excellent (r = 0.995). alpha-FP concentrations were measured by radioimmunoassay. DCP levels were raised in 66 of 98 patients (67.3%) and alpha-FP levels in 82 of 98 patients (83.7%) with hepatocellular carcinoma (P = 0.006). The specificity of DCP was also less than that of alpha-FP, although the difference just failed to reach statistical significance (P = 0.085). The predictive values of both a positive and a negative test for DCP were significantly less than those for alpha-FP (P = 0.047 and 0.048, respectively). When, in an attempt to eliminate false positive results, the diagnostic cut-off level for DCP was increased from 1.5 to 5.0 mu/ml and that of alpha-FP from 20 to 400 ng/ml, the differences between the two markers remained the same. If the two tests were used together, the number of false negative alpha-FP results was reduced from 16.3% to 7.1% and the number of equivocal alpha-FP results was reduced from 11.2% to 5.1%.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Hematology, South African Institute for Medical Research, Johannesburg.
authors.forename: M A
authors.initials: MA
authors.lastname: King
authors.forename: M C
authors.initials: MC
authors.lastname: Kew
authors.forename: J M
authors.initials: JM
authors.lastname: Kuyl
authors.forename: P M
authors.initials: PM
authors.lastname: Atkinson
mesh_terms: D015415:Biomarkers; D014408:Biomarkers, Tumor / Q000032:analysis*; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008101:Liver Abscess, Amebic / Q000175:diagnosis; D008107:Liver Diseases / Q000175:diagnosis; D008113:Liver Neoplasms / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D011498:Protein Precursors; D011516:Prothrombin / Q000031:analogs & derivatives* / Q000032:analysis; D012680:Sensitivity and Specificity; D000509:alpha-Fetoproteins / Q000032:analysis*
chemical_list: D015415:Biomarkers; D014408:Biomarkers, Tumor; D011498:Protein Precursors; D000509:alpha-Fetoproteins; C008208:acarboxyprothrombin; D011516:Prothrombin