KRAS and cancer: Feature selection using Least Absolute Shrinkage and Selection Operator (LASSO) was performed on 14 candidate biomarkers (6 exosomal mRNAs, 5 exosomal miRNAs, ctDNA KRAS MAF, circulating cell free DNA concentration and CA 19-9) to identify, train and validate optimal biomarker panels for distinguishing PDAC from non-cancer controls and for the differentiation of metastatic from non-metastatic PDAC.