Inflammatory pseudotumor of the liver caused by a migrated fishbone misdiagnosed as cholangiocarcinoma: a case report and literature review

Inflammatory pseudotumor of the liver secondary to a migrated fishbone is very rare. A 51-year-old man presented to our hospital with a 3-year history of vague epigastric pain, anorexia, and weight loss. Conventional abdominal ultrasound showed a hypoechoic mass in the left lobe of the liver, and contrast-enhanced ultrasonography indicated the typical enhanced pattern of fast-in-fast-washout. Both magnetic resonance imaging and computed tomography revealed a liver mass with progressive enhancement. Unenhanced computed tomography showed homogeneous hypo-attenuation with central calcification. Hematological examination revealed leukocytosis with granulocytosis. The initial diagnosis was cholangiocarcinoma accompanying inflammation. However, the pathological results revealed chronic non-specific inflammation on day 17 after admission. The patient’s symptoms recurred despite antibiotic treatment. Laparotomy was performed to establish a clear diagnosis, which revealed a foreign body (fishbone) embedded in the left lobe of the liver. Another biopsy confirmed an inflammatory lesion. The definitive diagnosis was inflammatory pseudotumor of the liver caused by a migrated fishbone. Surgeons and radiologists should be aware of liver inflammatory pseudotumor as a differential diagnosis in patients presenting with a hepatic mass, but with normal serum tumor markers and no specific history, especially in cases where there is discordance between imaging and histological results.