A resected case of giant pseudoglandular hepatocellular carcinoma that was challenging to distinguish from hepatic angiosarcoma, suspected to relate with exposure to vinyl chloride monomer

Abstract

An 80-year-old male patient had previously been exposed to vinyl chloride monomer (VCM) for 15 years (20-35 years old). At the consultation for accidental ingestion of press via pack (PTP), abdominal computed tomography (CT) showed 8 cm-in-diameter huge mass in liver S2/3, diagnosed as hepatic hemangioma. However, he was followed up closely because of a huge tumor. One month later, abdominal EOB-MRI revealed this tumor grown to 9.8 cm-in-diameter, and multiple small lesions were also discovered in liver, suspected to be a hemangiosarcoma. However, these might be HCC. For the purpose of diagnosis, left hepatic lobectomy was performed. Macroscopically, main tumor was filled with blood clots into the lumen. Histologically, these tumors were diagnosed to moderately distinguished HCC with pseudoglandular structures.

Imaging findings of pseudoglandular HCC were similar to those of hepatic hemangiomas. As a result, it should be noted that these lesions may grow even if identified with hepatic hemangiomas, particularly for cases associated with VCM exposure.