Differentiated adenocarcinoma in duodenum, a pathological subtype of duodenal tumors, accounts for more than 80% of duodenal tumors. Moderately differentiated adenocarcinoma, refers to the specific degree of differentiation of adenocarcinoma, such as highly differentiated adenocarcinoma, which is relatively less malignant because it is closer to the normal cell form; undifferentiated or hypodifferentiated adenocarcinoma, which is more malignant because it is closer to the primitive cells, has a worse relative prognosis than highly differentiated adenocarcinoma. Therefore, the above is the explanation for the differentiated adenocarcinoma of the duodenum.