Inflammatory pseudotumor of the liver: Radiologic diagnosis

To determine the characteristic radiologic findings of inflammatory pseudotumor of the liver, various imagings of ten patients (11 lesions) with proven diagnoses of inflammatory pseudotumor were reviewed. Radiologic examinations, i.e., computed tomography (CT; 11 lesions), ultrasonography (11 lesions), magnetic resonance imaging (MRI; 6 lesions), angiography (10 lesions), CT during arterio-portography (CTAP; 3 lesions), and gallium-67 scans (9 lesions) were analyzed for their utility in diagnosis. No inflammatory pseudotumor showed a fibrous capsule around the lesion. Ten of the 11 lesions were poorly demarcated on most of the imagings, and all 11 lesions showed delayed and/or prolonged enhancement on CT or MRI. Arterio-portal shunting was observed in 4 lesions after contrast material administration on CT or angiography. Central lesions with suspiciously high fibrotic tissue content were demonstrated in 5 lesions on CT or MRI. Major vessels coursing in the lesions were demonstrated in 4 lesions by CT, MRI, and CTAP. Inflammatory pseudotumor of the liver should be included in the differential diagnosis in patients with hepatic masses, even if the patients are asymptomatic. If radiologic examinations suggest inflammatory pseudotumor, percutaneous biopsies should be performed so that unnecessary surgery can be avoided.