Adenocarcinoma mimicking primary gastric lymphoma demonstrated by I-123 IMP scintigraphy.

A poorly differentiated adenocarcinoma of the stomach showed an unusual type of diffuse wall thickening of the entire stomach, similar to that seen in malignant lymphoma. The pathologic specimen revealed a "lymphoepithelioma"-like pattern of undifferentiated carcinoma with intense lymphocyte and plasma cell infiltration. I-123 IMP scintigraphy incidentally demonstrated increased uptake in the entire stomach on early imaging and moderate washout on delayed studies. SPECT images demonstrated diffusely increased accumulation in the entire gastric wall.