In this study, we evaluate the histological characteristics of CD-associated small bowel dysplasia/adenocarcinoma and investigate the therapeutic potential of CDH17 and CLDN18 for tumor-targeted immunotherapies, and also whether expression of both CDH17 and CLDN18 are related to gastric differentiation using gastric MUC immunostains, MUC5AC, and MUC6. This evidence concerns the gene CLDN18 and adenocarcinoma.