APOB mutations in familial hypobetalipoproteinemia presenting with cirrhosis and hepatocellular carcinoma in a Chinese male: A case report

BACKGROUND Familial hypobetalipoproteinemia (FHBL) is an autosomal codominant hereditary disorder resulting from mutations in the apolipoprotein B (APOB) gene.These mutations impair the secretion of lipoproteins, leading to hepatic triglyceride accumulation within hepatocytes.While hepatic steatosis is common among FHBL patients, progression to cirrhosis and hepatocellular carcinoma (HCC) is rare, particularly in East Asian populations.CASE SUMMARY A 62-year-old Chinese man with metabolic dysfunction-associated steatotic liver disease and cirrhosis secondary to FHBL.The diagnosis of HCC was made during routine surveillance.Genetic analysis identified three heterozygous APOB mutations: R2085*, Y2348C, and A3235S.Liver biopsy showed micronodular cirrhosis with mild steatosis affecting approximately 5% of the examined tissue.In March 2025, contrast-enhanced magnetic resonance imaging identified a 1.7-2.3cm hypervascular nodule in segment S8. Percutaneous biopsy of this lesion confirmed moderately to well-differentiated HCC.The patient subsequently received transarterial chemoembolization in March 2025.Subsequent imaging in April 2025 revealed two additional nodules (1.5 cm in segment S7 and 1.2 cm in segment S5), and microwave ablation was performed targeting all three lesions.The initial response was favorable, and no recurrence has been observed during follow-up.CONCLUSION FHBL may progress to HCC in the presence of coexisting metabolic disorders and specific APOB mutations.Genetic testing should be considered in patients with cryptogenic cirrhosis and low serum levels of low-density lipoprotein cholesterol or APOB.