Comparison between a new assay system, Elecsys® Anti-p53, and conventional MESACUP™ for the detection of serum anti-p53 antibodies: A multi-institutional study

The sensitivity and specificity of a new automated electrochemiluminescence immunoassay system, Elecsys® Anti-p53 (Elecsys), were compared with that of the conventional serum anti-p53 antibody (s-p53-Ab) enzyme-linked immunosorbent assay kit [MESACUP anti-p53 test (MESACUP)]. Elecsys and MESACUP were used to analyze the levels of s-p53-Abs in patients with esophageal, colorectal and breast cancer. A total of 532 controls and 288, 235 and 329 patients with esophageal, colorectal and breast cancer, respectively, were enrolled. Additionally, the sera of patients with benign diseases of the esophagus, colorectal system and breast, patients with autoimmune diseases and healthy volunteers were analyzed as controls. Sensitivity and specificity were compared between the two assay systems. Positive agreement rates were 58.7% in all samples, 71.2% in esophageal samples, 73.6% in colorectal samples and 35.1% in breast samples. Negative agreement rates for the different cancer types were ≥97.1% and the overall agreement rates were ≥92.3%. When the specificities of the two assays were aligned for all samples, Elecsys demonstrated higher sensi-tivities for all types of analyzed cancer together, as well as for esophageal, colorectal and breast cancer, respectively. Although positive concordance between the two assay systems was low in terms of specificity, Elecsys had a higher sensitivity than the MESACUP.