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Spontaneous complete necrosis of advanced hepatocellular carcinoma.

We present a rare case of hepatocellular carcinoma (HCC) in which spontaneous complete necrosis was confirmed with surgical resection. An 80-year-old man with HCC was referred to Nippon Medical School Tama Nagayama Hospital. The medical history included hypertension, managed with medication, and partial lobectomy of the lung owing to a lung schwannoma. A previously untreated abdominal aortic aneurysm, 51 mm in maximum diameter, was detected. The serum concentration of proteins induced by vitamin k antagonism or absence (PIVKA-2) was 14,300 mAU/mL, and that of alpha-fetoprotein was 184.2 ng/mL. Antibodies against hepatitis B surface antigens and hepatitis C virus were not detected in the serum. Computed tomography (CT) demonstrated a hypervascular tumor, 68 mm in diameter, in the left paramedian sector of the liver with washout of contrast medium in the delayed phase. An HCC in the left paramedian sector was diagnosed. Laparotomy was performed 40 days after CT scanning. Intraoperative ultrasonography showed that the HCC had shrunk to 30 mm in diameter. A left paramedian sectionectomy was performed. On macroscopic examination the surgical specimen was a firm mass, 30 mm in diameter, with a fibrous capsule. Histologic examination showed that the tumor in the cirrhotic liver had been completely replaced by central coagulative necrosis, circumferential fibrosis, and dense infiltrates of inflammatory cells. No viable HCC cells were observed in the coagulative necrosis. Organized thrombi in the hepatic artery were detected in the tumor. The tumor also contained multiple foci of old hemorrhage, ductular proliferation, and granulation tissue. The patient was discharged 10 days after the operation. After 1 month, the serum concentrations of PIVKA-2 (25 mAU/mL) and alpha-fetoprotein (5.9 ng/mL) had decreased to within their normal ranges.