A case of EBV-associated inflammatory pseudotumor of the spleen

Inflammatory pseudotumors (IPTs) of the spleen are rare and have often been reported to be associated with Epstein-Barr virus (EBV). Radiographically differentiating IPTs of the spleen from other malignant tumors is challenging, and splenectomy is often performed as a definitive treatment. We report a case of an EBV-associated splenic IPT in a male patient in his 70s. Contrast-enhanced computed tomography (CT) revealed a splenic mass that increased from 2.4 cm to 3.9 cm in diameter over one year. Magnetic resonance imaging (MRI) revealed that the mass showed a slightly high intensity on T1-weighted images and heterogeneous low intensity on T2-weighted images. On dynamic contrast-enhanced MRI, the mass showed weak and gradual inhomogeneous enhancement. A 18F-fluorodeoxyglucose (FDG) positron emission tomography/CT demonstrated increased FDG uptake in the mass. Splenectomy was performed and the pathological diagnosis was EBV-associated IPT. EBV-associated splenic IPT can mimic malignant tumors on imaging, making it challenging to differentiate them from other splenic diseases.