Necrosis of hepatocellular carcinoma caused by spontaneously arising arterial thrombus.

This paper describes a 65-year-old Japanese man with hepatocellular carcinoma (HCC) in whom the alpha-fetoprotein level decreased remarkably without any treatment. Plain computed tomography disclosed a low-density area in the left lateral segment. Liver scintigraphy revealed a filling defect with 99mTc-Sn colloid and increased uptake of 67Ga-citrate. The latter was smaller in area than the former. This indicates that non-necrotic HCC was still present at this time. There was no hypervascular lesion in the hepatic angiogram obtained 22 days after liver scintigraphy. The tumor was resected by partial hepatectomy 24 days after hepatic angiography. The histological section showed almost complete necrotization of the tumor, and the necrotic change consisted of old and recent necrosis. An arterial thrombus was formed in non-tumor liver tissue. It was presumed that coagulative necrosis was produced by interruption of the blood supply due to the spontaneous formation of an arterial thrombus.