Hepatic inflammatory pseudotumor associated with primary biliary cholangitis and elevated alpha-fetoprotein lectin 3 fraction mimicking hepatocellular carcinoma

BACKGROUND: Hepatic inflammatory pseudotumor (IPT) is a rare benign lesion. Because there is no specific laboratory marker or radiographic appearance, the majority of reported cases of hepatic IPT have been diagnosed after surgery or at autopsy. The etiology of hepatic IPT remains unclear but several mechanisms have been postulated such as infection or immune reaction. CASE PRESENTATION: A 79-year-old woman had been seeing her family doctor for hypertension, and she had been diagnosed with liver dysfunction for about 10 years. She continued attending follow-ups because of her drinking habit. Two months before her visiting our institution, further elevation of hepatobiliary enzymes was noted, and abdominal ultrasonography showed a hepatic tumor 4 cm in diameter in the lateral segment, so she was referred to our hospital. Hepatocellular carcinoma (HCC) was suspected because alpha-fetoprotein (102 ng/ml) (AFP) and lectin 3 (L3) fraction (85.4%) were elevated and the appearance on enhanced computed tomography was not inconsistent with HCC. Thus, we performed laparoscopic hepatectomy. She recovered uneventfully and was discharged on postoperative day 7. Pathological diagnosis revealed that the tumor was hepatic IPT and that the background liver condition was primary biliary cholangitis (PBC). AFP and L3 fraction decreased to normal ranges after surgery. CONCLUSIONS: In 7 of 29 patients (24.1%) with reported cases of tumor markers in liver IPT, carbohydrate antigen 19-9 was elevated and AFP was elevated in 2 of 58 patients (3.4%). AFP is also frequently elevated in benign liver diseases such as hepatitis and liver cirrhosis, and L3 fraction has been used as a tumor marker for HCC with high specificity. To our knowledge, this is the first report of a case diagnosed with liver IPT in which AFP and L3 fraction increased before surgery and decreased to the normal range after resection. This confirms the rarity of hepatic IPT associated with PBC and elevated AFP and L3 fraction.