Two elder cases of hepatocellular carcinoma adjacent to intrahepatic vessels successfully treated by carbon ion radiotherapy.

The treatment for hepatocellular carcinoma (HCC) adjacent to the portal vein and/or bile duct requires considerable caution to avoid the complications, such as hepatic infarction and obstructive jaundice. Carbon ion radiotherapy (CIRT) has been attempted for HCC and has become accepted as a promising modality for minimizing hepatic damage with good local tumor control. We experienced two elder cases of HCC adjacent to intrahepatic vessels successfully treated by CIRT. Case 1, a 75-year-old man, was treated by CIRT for a 2-cm HCC near the porta hepatis adjacent to the right first portal branch. The treatment was sufficiently effective, and no vascular damage was demonstrated after CIRT. The liver function transiently deteriorated after CIRT, but recovered quickly. Alpha-fetoprotein transiently increased after the treatment and decreased thereafter. Tumor stain persisted for 3 months after CIRT, so a liver tumor biopsy was performed. However, no viable carcinoma cells were detected. There was no local recurrence or complications for 17 months. Case 2, 76-year-old male HCC patient, showed dilation of the peripheral bile duct in the left lobe, suggesting tumor invasion to the duct. The tumor was hypovascular and was found to be well-differentiated HCC by a tumor biopsy. He was treated with CIRT, because he had a history of cerebral infarction and was being administered an antiplatelet agent daily. He achieved complete remission, and no adverse events were observed after the treatment for 3 years.