Inflammatory pseudotumour of spleen

A case of inflammatory pseudotumour of spleen in which plasma cells were the predominant cell type, is described. It presented as multiple nodules in the spleen of a 37 year old woman who died of myocardial infarction, and was an incidental finding at necropsy. Plasma cells were the dominant cell type, and the admixture of other cells within the mass and the lack of a monotypic light chain/immunoglobulin phenotype on immunohistochemical analysis precluded a diagnosis of malignant disease. The potential for misinterpretation of this lesion as a neoplasm is considerable and its recognition may therefore be of great clinical importance.