[Gastric amyloidosis mimicking malignancy. A case report].

Amyloidosis is an abnormal extracellular deposition of insoluble proteins, which is associated with an involvement of the gastrointestinal tract in 50 to 70% of cases. In primary amyloidosis (light chain amyloidosis), localized gastric involvement is a rare finding which can mimic malignancy. We report the case of a 56-year-old man, admitted with upper digestive outlet obstruction. Linitis plastica with lymph node involvement was suspected by gastroscopy, barium meal and endoscopic ultrasonography but was not confirmed by gastric biopsies. The patient was treated with total gastrectomy with lymph node dissection. Pathological examination demonstrated gastric and lymph nodes amyloidosis and no malignant tumor was found. The patient died 9 months later from cardiac failure due to amyloidosis.