MUC5AC and familial pancreatic carcinoma: The evidence available on MUC5AC reactive to NPC-1C and PAM4 antibody suggests that both the Mabs stain or react to a specific epitope (on MUC5AC) that is (a) not expressed in normal pancreatic tissues; (b) detected in most malignant pancreatic and colon tissues; (c) different from the targets of anti-MUC5AC monoclonal antibodies such as CLH2, 45-M1, and 2-11M used to detect native MUC5AC; and d) detected in the serum of pancreatic cancer patients (summarized in Table 3).