目的:了解原发性十二指肠降部癌内镜及临床特点。方法:根据临床表现、胃镜及活检组织病理检查分析4例原发性十二指肠降部癌的临床资料。结果:内镜检查3例为息肉型,1例为溃疡型,病理类型均为腺癌,3例行胰十二指肠切除术,1例因有远处转移,全身情况差,未行手术。结论:原发性十二指肠恶性肿瘤较少见,该疾病早期诊断困难,预后差,及时、全面的内镜检查是提高本病诊断率的关键。 Objective: To understand the primary endoscopic descending colon cancer and clinical features. Methods: According to clinical manifestations, endoscopy and biopsy histopathological examination of 4 cases of primary duodenal hypogastric cancer clinical data. Results: Three cases of endoscopic examination were polypoid type, one was ulcer type, the pathological type was adenocarcinoma, three cases had pancreatoduodenectomy, one case had distant metastasis, the general condition was poor, and no operation . Conclusion: Primary duodenal malignancies are rare, early diagnosis of the disease is difficult, the prognosis is poor, timely and comprehensive endoscopy is the key to improve the diagnostic rate of the disease.