The authors report two cases of duodenal adenocarcinoma. Review of literature has permitted them to conclude the rarity of the lesion which among malignant tumours of the small intestine, is the gommenest. Localization of the tumour in the periampullary area in 47% of cases rendered it difficult to differentiate from ampullary and pancreatic tumours especially with the unknown etiological factors (with exception to villous tumours which has a 35% rate of malignant transformation), and also with unspecific symptoms. Diagnosis by x-ray and endoscopy has an accuracy rate of more then 85%. Prognosis is bad and depend mainly on histological differentiation and lymph node spread. 5 years survival rate of 40-50% can be achieved by curative surgery namely cephalic duodeno-pancreatectomy in cases with no lymph node involvement.