Sarcomatoid hepatocellular carcinoma mimicking hepatic abscess: A case report

RATIONALE: Primary sarcomatoid hepatocellular carcinoma (SHC) is a rare subtype of morphologic hepatocellular carcinoma reported on less than 1% of surgical pathology specimens. Herein, we report a rare case of SHC. The case in question was initially misdiagnosed as a liver abscess due to the clinical and radiological similarity between these 2 pathologies. Ultrasound(US)- and contrast-enhanced ultrasound (CEUS)- guided biopsies are helpful in making an accurate diagnosis under the appropriate biopsy area and angle of puncture. PATIENT CONCERNS: A 56-year old male presented to our hospital with a 2-month history of dull, upper abdominal pain without radiation. DIAGNOSES: Upon initial investigation with computed tomography, a cystic mass was found in the hepatic V segment and an infectious etiology was presumed. Further diagnostic examination with CEUS and magnetic resonance imaging suggested a hepatic abscess. However, a diagnosis of atypical intrahepatic cholangiocarcinoma was not excluded. The patient received the standard antibiotic treatment without alleviation of his symptoms. Through 3 diagnostic US-and CEUS-guided biopsies over a 3-month period, the pathological diagnosis of SHC was finally confirmed. INTERVENTIONS: The patient was diagnosed by 3 diagnostic US-and CEUS-guided biopsies, the pathological diagnosis of SHC was finally confirmed. OUTCOMES: Due to the delay in diagnosis, the patient was not a candidate for surgical resection, and showed dissemination of the lesion to the portal vein. Therefore, treatment with chemotherapy was initiated. After 4 courses of this regimen, tumor progression was found on enhanced magnetic resonance imaging. Therefore, the patient received immunotherapy and targeted therapy with limited response. The patient passed away 3 months later due to tumor progression. LESSONS: A hepatic abscess should be considered as a malignant lesion when clinical symptoms do not resolve upon standard treatment. US- and CEUS- guided biopsies are helpful in making an accurate diagnosis under the appropriate biopsy area and angle of puncture.