Biological variations of seven tumor markers

Abstract

BackgroundWe sought to identify biological variations in the following tumor markers: pepsinogen I (PGI), pepsinogen II (PGII), carbohydrate antigen 724 (CA724), neuron-specific enolase (NSE), pro-gastrin-releasing peptide (ProGRP), carcinoembryonic antigen (CEA), and carbohydrate antigen 199 (CA199). MethodsSerum samples were collected from 20 healthy Chinese individuals over 5days. Samples were then screened for the presence of the seven aforementioned tumor markers. Within-individual coefficient of variation (CVI), between-individual coefficient of variation (CVG), confidence interval (CI) of biological variations, index of individuality (II), and the reference change value (RCV) of the seven tumor markers were calculated. ResultsOf the 7 tumor markers, index of individuality was all <1.0. ProGRP showed the lowest CVI and CVG, at 4.75% (CI: 3.96%–5.94%) and 16.42% (CI: 12.32%‐24.61%), respectively. The 95% and 99% RCVs for ProGRP were 14.68 and 19.32, respectively, and were the lowest of the markers. In contrast, the CVI and CVG for CA724 were the highest, at 16.06% (CI: 13.83%–19.17%) and 96.95% (CI: 73.73%–141.59%), respectively. The 95% and 99% RCVs for CA724 were the highest, at 45.89 and 60.41, respectively. ConclusionOur findings provide additional information regarding the biological variation of tumor markers, and could be applied in a clinical setting.