Enzyme-Linked Immunosorbent Assay (ELISA) evaluation for cancer antigens

Abstract

This research evaluated the diagnostic performance of sandwich ELISA protocols for detecting five cancer antigens: CEA, CA 19-9, CA 125, AFP, and PSA. Serum samples were collected from 53 cancer patients and 47 healthy controls at John Radcliffe Hospital, Oxford, between March 2021 and November 2022. Results indicated markedly elevated antigen concentrations in cancer patients. CEA showed 3.8-fold increase (8.7 versus 2.3 ng/mL), CA 19-9 demonstrated 3.6-fold elevation (67.3 versus 18.7 ng/mL), and CA 125 exhibited 6.3-fold increase (89.4 versus 14.2 ng/mL). ROC analysis revealed AUC values ranging from 0.823 for CEA to 0.934 for combined multi-marker panels. The combined approach achieved 91.4% sensitivity and 87.2% specificity. Inter-assay and intra-assay coefficients of variation remained below 8.3% and 5.7% respectively. These findings support ELISA-based cancer antigen detection, particularly with multi-marker strategies.