Primary small intestinal carcinomas are very rare, but the majority of those that do occur arise in the region of the ampulla, where they may become symptomatic through biliary or pancreatic duct obstruction.

• 原发性小肠腺癌很少见，但大部分发生在壶腹区域，在那里它们通过堵塞胆汁和胰液的输送而产生症状。