A pilot study of three-dimensional conformal radiotherapy in unresectable hepatocellular carcinoma

Background: The purpose of this study was to determine the potential role of three-dimensional (3-D) conformal radiotherapy (RT) in treatment of unresectable hepatocellular carcinoma (HCC). Methods: Thirteen patients were included in this study, which was conducted between 1993 and 1996. Nine patients (group A) were treated with 3-D conformal RT alone because of main portal vein thrombosis, inferior vena cava thrombosis, obstructive jaundice and failure of previous transcatheter arterial chemoembolization (TACE) to control the disease. The remaining four patients (group B) were treated with a combination of TACE and 3-D conformal RT. Results: The greatest dimension of the main tumour in the whole group of patients ranged from 6 to 25 cm (median 15 cm). The radiation dose ranged from 40 to 60 Gy. The tumour response was evaluated by computed tomography scans of the liver 6-8 weeks after completion of radiotherapy. Partial response was observed in 58% of the patients (seven of 12) and minimal response in another 25% of patients (three of 12). One patient could not be evaluated because of the development of hepatic failure 1 month after completion of RT. All patients in group B lived for more than 1 year (range 16-40 months). In group A, one patient who had a large tumour (11 x 10 x 21 cm) with portal vein thrombosis was converted to become resectable after 45 Gy of radiation. The resection specimen revealed no residual cancer cells. This patient is alive longer than 15 months after treatment without the evidence of disease. Conclusions: Our experience indicates that HCC is more radiosensitive than it was traditionally expected. Three-dimensional reconstruction of tumour and surrounding organs helps to avoid excessive exposure of the liver and adjacent organs to RT and makes it a safer treatment modality for unresectable HCC. Our preliminary data show promise and are worthy of further study to explore the potential role of radiotherapy in the treatment strategy for HCC at various stages of involvement. (C) 1999 Blackwell Science Asia Pty Ltd.