Acta Medica Okayama 71巻 1号
2017-02 発行
Fukugawa, Yoshiyuki
Department of Radiation Oncology, Kumamoto University Hospital
Namimoto, Tomohiro
Department of Diagnostic Radiology, Kumamoto University Hospital
Toya, Ryo
Department of Radiation Oncology, Kumamoto University Hospital
Saito, Tetsuo
Department of Radiation Oncology, Kumamoto University Hospital
Yuki, Hideaki
Department of Diagnostic Radiology, Kumamoto University Hospital
Matsuyama, Tomohiko
Department of Radiation Oncology, Kumamoto University Hospital
Ikeda, Osamu
Department of Diagnostic Radiology, Kumamoto University Hospital
Yamashita, Yasuyuki
Department of Diagnostic Radiology, Kumamoto University Hospital
Oya, Natsuo
Department of Radiation Oncology, Kumamoto University Hospital
Focal liver reaction (FLR) appears in the hepatobiliary-phase images of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA-enhanced MRI) following radiotherapy (RT). We investigated the threshold dose (TD) for FLR development in 13 patients with hepatocellular carcinoma (HCC) who underwent three-dimensional conformal radiotherapy (3D-CRT) with 45 Gy in 15 fractions. FLR volumes (FLRVs) were calculated based on planning CT images by referring to fused hepatobiliary-phase images. We also calculated the TD and the irradiated volumes (IVs) of the liver parenchyma at a given dose of every 5 Gy (IVdose) based on a dose-volume histogram (DVH). The median TD was 35.2 Gy. The median IV20, IV25, IV30, IV35, IV40, and IV45 values were 371.1, 274.8, 233.4, 188.6, 145.8, and 31.0 ml, respectively. The median FLRV was 144.9 ml. There was a significant difference between the FLRV and IV20, IV25, and IV45 (p<0.05), but no significant differences between the FLRV and IV30, IV35, or IV40. These results suggest that the threshold dose of the FLR is approx. 35 Gy in HCC patients who undergo 3D-CRT in 15 fractions. The percentage of the whole liver volume receiving a dose of more than 30-40 Gy (V30-40) is a potential candidate optimal DVH parameter for this fractionation schedule.
Gd-EOB-DTPA
hepatocellular carcinoma
magnetic resonance imaging
radiation-induced liver disease
radiotherapy