LCN2 and serous cystadenoma: In the first step, the expression of biomarkers miR-196b, LCN2, TIMP1, RNU2-1f, and CA 19-9 was analyzed in 116 serum samples of patients or IAR who underwent pancreatic resections for PDAC (n = 50, 5 stage I, 38 stage II and 7 stage III), FPC (n = 20, 6 stage II, 1 stage III and 13 stage IV), CP (n = 10), significant lesions (n = 5), potentially relevant lesions (n = 6), non-relevant lesions such as multifocal PanIN1 or serous cystadenoma (n = 5), and healthy controls (n = 20), respectively.