Pancreatic ductal adenocarcinoma (PDAC) is considered as one of the most aggressive cancers lacking efficient early detection biomarkers. Circulating miRNAs are now being considered to have potency to be used as diagnostic and prognostic biomarkers in different diseases as well as cancers | Comparison of tumour and serum specific microRNA changes dissecting their role in pancreatic ductal adenocarcinoma A metaanalysis