INTERLABORATORY SURVEYS OF THE DETERMINATION OF TUMOR-MARKERS SCATTERAND REPEATABILITY OF THE RESULTS

Data collected between 1983 and 1991 in interlaboratory surveys of the determination of tumour markers are used to show the magnitude of the scatter of results from different laboratories for the analysis of a single quantity in a given matrix. These data also show that the varyi ng specificity of different reagent combinations appears to make a con siderable contribution to this scatter, and that the used reagent comb inations were not of uniform quality over a relatively extended period . The results for the following tumour markers were studied: alpha-fet oprotein (AFP), carcinoembryonic antigen (CEA), human chorionic gonado tropin (hCG), human chorionic gonadotropin + beta-subunit (hCG + beta- hCG), tissue polypeptide antigen (TPA), carbohydrate antigen 19-9 (CA 19-9), cancer antigen 15-3 (CA 15-3), cancer antigen 125 (CA 125), pro static acid phosphatase (PAP) and prostate-specific antigen (PSA).