[Signet-ring-cell lymphoma. Light and electron microscopic study of gastric involvement]

The authors report on a malignant Non-Hodgkin lymphoma of the stomach of a 73-year-old male. Histologically, it was revealed to be a follicularly growing, obviously secondary centroblastic lymphoma. Crystalline cytoplasmic inclusions in numerous centrocytes have led to displacement of the nucleus to the cell margin and thus to the picture of a signet-ring-cell lymphoma. Electronmicroscopically, there were found big crystalline electron-dense deposits in the rough endoplasmic reticulum. The finding was compared with literature data, and the histological differential diagnosis is discussed.