EGFR and colorectal cancer: To our knowledge, no specific molecular change is shared by the full spectrum of PaCS-positive cells and neoplasms we have observed, with the possible exception of MAPK-ERK pathway activation [16], [17], either through EGFR overexpression/activation, as in H. pylori-infected gastric cells [18] and in pancreatic serous cystic adenoma [19], or through constitutive ERK activation, often secondary to EGFR, RAS or BRAF mutation, as found in hepatocellular, lung, thyroid papillary, ovarian and colorectal cancers [20]–[24].