title: Single photon emission computed tomography-based three-dimensional conformal radiotherapy for hepatocellular carcinoma with portal vein tumor thrombus.
abstract: OBJECTIVE
  To evaluate the safety and efficacy of three-dimensional conformal radiotherapy (3D-CRT) using single photon emission computed tomography (SPECT) in unresectable hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT).
  
  
  METHODS
  Patients with HCC with PVTT in the first branch and/or main trunk were selected for this study. The optimal beam directions for 3D-CRT were explored using a Tc-99m-galactosyl human serum albumin SPECT image for guidance. The SPECT image was classified as either wedge type or localized type. The clinical target volume to a total dose of 45 or 50 Gy per 18-20 fractions included the main tumor and PVTT in the wedge type and PVTT alone in the localized type.
  
  
  RESULTS
  Twenty-six patients were enrolled: 18 with wedge type and 8 with localized type. Mean tumor size was 7.1 cm (range, 4.4-12.3 cm). Clinical target volumes of wedge type vs. localized type were 111.2 cm(3) vs. 48.4 cm(3) (p = 0.010), respectively. Mean dose to normal liver and mean dose to functional liver were 1185 cGy and 988 cGy (p = 0.001) in wedge type and 1046 cGy and 1043 cGy (p = 0.658) in localized type, respectively. Despite an incidence of Child-Pugh B and C of 57.7%, no patients experienced radiation-induced liver disease. The progression of PVTT was inhibited, with an incidence of 92.2%; survival rates at 1 and 2 years were 44% and 30%, respectively.
  
  
  CONCLUSIONS
  Single photon emission computed tomography-based 3D-CRT enables irradiation of both the main tumor and PVTT with low toxicity and promising survival.
authors.affiliation: Department of Radiology, Wakayama Medical University, Wakayama Shi, Wakayama, Japan.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Shirai
authors.forename: Morio
authors.initials: M
authors.lastname: Sato
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Suwa
authors.forename: Kazushi
authors.initials: K
authors.lastname: Kishi
authors.forename: Chigusa
authors.initials: C
authors.lastname: Shimono
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kawai
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Tanihata
authors.forename: Hiroki
authors.initials: H
authors.lastname: Minamiguchi
authors.forename: Motoki
authors.initials: M
authors.lastname: Nakai