Superiority of helical tomotherapy on liver sparing and dose escalation in hepatocellular carcinoma: a comparison study of three-dimensional conformal radiotherapy and intensity-modulated radiotherapy

Qianqian Zhao,1,2 Renben Wang,2 Jian Zhu,2 Linzhi Jin,1,2 Kunli Zhu,2 Xiaoqing Xu,2 Rui Feng,2 Shumei Jiang,2 Zhonghua Qi,1,2 Yong Yin2 1School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Sciences, 2Department of Radiation Oncology, Shandong Cancer Hospital affiliated to Shandong University, Jinan, People’s Republic of China Background and purpose: To compare the difference of liver sparing and dose escalation between three-dimensional conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT), and helical tomotherapy (HT) for hepatocellular carcinoma.Patients and methods: Sixteen unresectable HCC patients were enrolled in this study. First, some evaluation factors of 3DCRT, IMRT, and HT plans were calculated with prescription dose at 50Gy/25 fractions. Then, the doses were increased using HT or IMRT independently until either the plans reached 70Gy or any normal tissue reached the dose limit according to quantitative analysis of normal tissue effects in the clinic criteria.Results: The conformal index of 3DCRT was lower than that of IMRT (P IMRT > HT (P