Efficacy of preoperative radiotherapy to portal vein tumor thrombus in the main trunk or first branch in patients with hepatocellular carcinoma

Background The prognosis of hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT) in the main trunk or the first branch is very poor. Methods. Radiotherapy (RT) to PVTT was followed by hepatectomy within 2 weeks. The dose used was 30-36 Gy, in 10-12 fractions, for 15-20 days. The efficacy of preoperative RT to PVTT in the main trunk or first branch was evaluated by comparing results in patients who underwent hepatectomy (group R; n = 15) with preoperative RT and those without preoperative RT (group N; n = 28). Results. The 1-, 3-, and 5-year survival rates in group R were 86.2%, 43.5%, and 34.8%, respectively, while these values in group N were 39.0 %, 13.1 %, and 13.1 %, respectively. The survival curve of group R was significantly better than that of group N (P = 0.0359). In group R, five (83.3 %) of six patients whose tumor thrombus was completely necrosed (based on pathological examination) and whose follow-up period was over 2 years survived for more than 2 years. Female sex (P = 0.0066), multiple tumors (P = 0.0369), and absence of preoperative RT (P = 0.0359) were ranked as significant factors for a poor prognosis by univariate analysis. Multivariate analysis revealed absence of preoperative RT and female sex to be significant factors for a poor prognosis. Conclusion. Preoperative RT to PVTT in the main trunk or first branch improved the prognosis of patients with HCC with PVTT, and could be a promising new modality in the treatment of these patients.