Inflammatory pseudotumor of the liver. Clinicopathologic study and review of the literature.

Clinicopathologic analysis of nine patients with inflammatory pseudotumor of the liver was reported. The age of the patients varied from 22 to 83 years old, with a male to female ratio of 8 to 1. They complained of intermittent fever and abdominal pain, and laboratory data on admission suggested an inflammatory process. The solitary or multiple, well-defined space-occupying lesions were displayed by recently advanced imaging techniques. Partial hepatectomy, laparotomy, needle biopsy, or autopsy was performed in all nine patients with diagnoses of hepatocellular carcinoma, metastatic liver tumor, or liver abscess. Histologically, these lesions were composed of dense hyalinized fibrosis and/or infiltrating inflammatory cells constituting large numbers of foamy histiocytes, lymphocytes, and plasma cells. Obliterating phlebitis of relatively large branches of the portal vein was found, thus providing a diagnostic clue to distinction from the primary hepatic cancer by imagings. Considering the clinicopathologic features and the patients' histories, in which four patients had been in the Southeast Asian countries or India, it is possible that infection of microorganisms through the portal vein could participate in these lesions as a cause. Two patients died of causes probably related to this lesion, indicating poor prognosis in some patients, in contrast to the generally fair prognosis of previously published cases.