Immunophenotype of Ampullary Carcinoma and Periampullary Carcinoma in Relation to Histogenesis of Pancreatoduodenal Region

The aim was to study the morphology of the pancreas in embryogenesis and to analyze the immunophenotype of ductal adenocarcinoma (DA) and ampullary carcinoma (AC), taking into account the data obtained. Material and methods . The analysis of operative material of 30 patients with AC and 100 patients with DA was performed. To study the embryogenesis of the pancreas, 14 abortive human embryos were studied. The work used general histological and immunohistochemical methods of investigation. Results. Analyzing the morphology of the pancreas of human embryos at different times of gestational development, we came to the conclusion, that the pancreatobiliary epithelium type is more specialized. Pancreatobiliary tumor immunophenotype was detected in 61% of cases of DA. In 28% of cases (28/100) gastric immunophenotype of DA was detected, which is characterized by expression of mucin 5AC type. Only 11% intestinal immunophenotype of a tumor with isolated expression of mucin type 2 (cytoplasmic reaction) was revealed. In the study of AC, the material was distributed as follows: group with an intestinal phenotype was 60%; with pancreato-biliary type - 33.3%. Conclusion. We believe that for DA with intestinal immunophenotype, it is unacceptable to apply the same treatment regimen as for AC, since this cancer does not have a full intestinal differentiation, but acquires only a similar immunohistochemical profile. In contrast, for AC with pancreatobiliary immunophenotype, the use of standard regimens based on gemcitabine is justified, because these tumors evolve from the hybrid epithelium and retain all the properties of the pancreatobiliary epithelium.