Autoantibodies as Potential Liquid Biopsy Biomarker in Detection of Pancreatic Cancer: A Diagnostic Test Accuracy Review and Meta-Analysis.

Autoantibodies against tumour-associated antigens (TAA) are promising biomarkers for cancer diagnosis. This systematic review aims to evaluate the diagnostic values of tumour-associated autoantibodies (TAAbs) in patients with pancreatic cancer. A search was conducted in the PubMed, Web of Science, and Embase databases to collect eligible studies. The primary outcomes included sensitivity, specificity, and accuracy of the test. We used QUADAS-2 to evaluate the risk of bias in the included studies. Meta-analysis was performed using MetaDisc 1.4 and STATA 14.0 software to calculate the combined sensitivity and specificity. A total of 49 articles were included in the final analysis that reported over 100 different TAAbs that were studied for the detection of pancreatic cancer. p53, Ezrin, CLDN17, KCNN3, SLAMF7, SLC22A11 and OR51F2 were the most frequently investigated autoantibodies in these studies. Ezrin exhibited better diagnostic performance with the pooled sensitivity, specificity and summary area under the receiver operating characteristic (SROC) curves being 56%, 88% and 0.90, respectively. Moreover, certain autoantibody combinations achieved substantially higher sensitivity at reasonably high levels of specificity. For example, the combination of Ezrin and ENOA1.2 autoantibodies with CA19.9 yielded sensitivity, specificity and area under the SROC curve of 100%, 92% and 0.96, respectively. TAAb is a promising diagnostic biomarker for early detection of PC, especially when combining TAAb with other markers. The promising candidate markers identified in this review deserve further validation in a broad screening population.