Three-dimensional conformal radiotherapy for portal vein tumor thrombosis alone in advanced hepatocellular carcinoma

Purpose: Hepatocellular carcinoma (HCC)with portal vein tumor thrombosis(PVTT)has poor prognosis. The aim of this study was to investigate the efficacy and prognostic factors of conformal radiotherapy for PVTT in unresectable HCC. The primary endpoint of this study is the overall survival of patients. The secondary endpoint is the overall response of tumors. Patients and Methods: form June 1998 to December 2001, 23 patients of advanced HCC with PVTT enrolled into the study. Mean treatment dose was 47.6 ±4.4 Gy, in a daily fraction of 1.8-2.2 Gy. Response was assessed by enhanced computer tomography (CT) scan and/or color Doppler abdominal ultrasonography 2-4 weeks following completion of the treatment and then in a 2-4 month interval. Survival was calculated from the diagnosis of PVTT using the Kaplan-Meier method. Results: An objective response was observed in 9 patients, giving a response rate of 39%. The survival rate of the responder patients was significant higher than non-responders(median survival 13 vs. 5 months, p=0.0027). All of the 9 responders received sub-sequent transcatheter arterial chemoembolization (TACE) or percutaneous ethanol injection (PEI). Multivariate analysis showed that the response of PVTT and the subsequent treatments were the prognostic factors of the survival, while the pre-treatment hemoglobin and serum albumin level were the factors that affected response. The intervals from the completion of radiotherapy to response ranged from 10 to 255 days(median 17 days). Conclusion: Local conformal irradiation to PVTT is sometimes feasible and effective. Better nutritional status reflected by the hemoglobin and serum albumin levels improves response rates and prolongs survival consequent to subsequent TACE or PEI.