Spontaneous regression of hepatocellular carcinoma repeated 3 times with invasion of portal vein and inferior vena cava: report on a rare case.

A 65-year-old man suffered from advanced hepatocellular carcinoma in the right lobe of the liver, for which he received no treatment. His serum was positive for hepatitis C antibody. In spite of his poor prognosis, he remained in good clinical condition and at 6-month follow-up the tumor had regressed without specific treatment, as assessed both radiologically and from a decrease of a previously elevated serum tumor marker level (1st regression). The tumor regrew in size, but at 23-month follow-up could no longer be visualized radiologically (2nd regression). A follow-up computed tomography (CT) scan did not show any relapse of hepatocellular carcinoma until March 2005. At that time, a new lesion had developed in the caudate lobe and tumor size had increased to ≥10 cm in diameter, and in June 2006 had invaded the portal vein and inferior vena cava. Afterwards, the tumor lesion gradually decreased again. In June 2007, a CT scan showed a further reduction of tumor size (3rd regression). Here, we report a rare case of spontaneous regression of hepatocellular carcinoma in which spontaneous regression and recurrence were repeated 3 times.