Inflammatory pseudotumour of the spleen: imaging findings

The term ‘inflammatory pseudotumour’ (IPT) is used for a variety of chronic sclerosing inflammatory processes with a distinct histopathological appearance. The lung and the liver have been reported as the most common sites . Splenic involvement is extremely rare . Splenic IPT is a benign condition of unknown aetiology and pathogenesis that should not be confused with a neoplasm. However, it can mimic either clinically or radiologically other splenic neoplasms. Clinically, the symptoms of splenic IPT are mostly non-specific, such as left flank or left upper quadrant abdominal pain, or the lesion may be detected as an incidental finding, as in the case reported .In our case, non-enhanced CT examination revealed a hypodense mass without calcification. After intravenous contrast medium injection there was a poor homogeneous enhancement. The lesion appears sonographically as a hypoechoic lesion, not typical for a cyst.The only tool to differentiate a neoplastic process of the spleen from splenic IPT is the histopathological examination of the surgical specimen:The histological findings showed polymorphic inflammatory cell infiltrate and proliferation of spindle cells. Inflammatory cells present include lymphocytes, plasma cells, histiocytes along with neutrophils and eosinophils. Spindle cells are positive for vimentin confirming their myofibroblastic origin