SMAD4 and pancreatic neoplasm: Now main current view summarizes the occurrence of pancreatic cancer as a consecutive biological event: Kras mutation and Her2 overexpression could cause intraepithelial neoplasia of the pancreas, tumor suppressor genes p16, p53, DPC4 and BRCA2 may dysfunction in the immunol suppressive microenviroment, eventually leading to pancreatic cancer.