High dose radiotherapy with image-guided hypo-IMRT for hepatocellular carcinoma with portal vein and/or inferior vena cava tumor thrombi is more feasible and efficacious than conventional 3D-CRT

OBJECTIVE: To compare the efficacies of conventional three-dimensional conformal radiotherapy and image-guided hypofractionated intensity-modulated radiotherapy treatments in advanced hepatocellular carcinoma patients with portal vein and/or inferior vena cava tumor thrombi. METHODS: A total of 118 hepatocellular carcinoma patients with portal vein and/or inferior vena cava tumor thrombi who received external beam radiation therapy focused on tumor thrombi and intrahepatic tumors were retrospectively reviewed. During the three-dimensional conformal radiotherapy treatments, a median total dose of 54 Gy with a conventional fraction (1.8-2.0 Gy/fx) was delivered. During the image-guided hypofractionated intensity-modulated radiotherapy treatments, a median total dose of 60 Gy with fractions of 2.5-4.0 Gy/fx was delivered. RESULTS: The median follow-up time was 11.8 months (range, 1.7-43.7 months). Higher radiation doses were delivered by image-guided hypofractionated intensity-modulated radiotherapy than by three-dimensional conformal radiotherapy (average dose 57.86 ± 7.03 versus 50.88 ± 6.60 Gy, P ≤ 0.001; average biological effective dose 72.35 ± 9.62 versus 61.45 ± 6.64 Gy, P < 0.001). A longer median survival was found with image-guided hypofractionated intensity-modulated radiotherapy than with three-dimensional conformal radiotherapy (15.47 versus 10.46 months, P = 0.005). Multivariate analysis showed that image-guided hypofractionated intensity-modulated radiotherapy is a significant prognostic factor for overall survival. Toxicity was mild for both image-guided hypofractionated intensity-modulated radiotherapy and three-dimensional conformal radiotherapy. CONCLUSIONS: High dose radiotherapy delivered by image-guided hypofractionated intensity-modulated radiotherapy appears to be an effective treatment that provides a survival benefit without increasing severe toxicity in hepatocellular carcinoma patients with portal vein and/or inferior vena cava tumor thrombi.