Jing Sun,1,* Hao-ran Lu,1,* Jian-hui Wu,2,* Dong Li,1,* Tao Zhang,1 Xue-zhang Duan1 

1Department of Radiation Oncology, Senior Department of Oncology, The Fifth Medical Center of PLA General Hospital, Beijing, People’s Republic of China; 2Medical School, Chinese PLA General Hospital, Beijing, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Xue-zhang Duan, Department of Radiation Oncology, Senior Department of Oncology, The Fifth Medical Center of PLA General Hospital, No. 100 Xi Si Huan Middle Road, Fengtai District, Beijing, 100039, People’s Republic of China, Tel +8613621386161, Email duanxuezhang@301hospital.com.cn Tao Zhang, Department of Radiation Oncology, Senior Department of Oncology, The Fifth Medical Center of PLA General Hospital, No. 100 Xi Si Huan Middle Road, Fengtai District, Beijing, 100039, People’s Republic of China, Tel +86 13641304338, Email 13641304338@126.com

Abstract: Radiation therapy is one of the main methods of tumor treatment, with over 50% of patients opting for it during treatment. The optimal regimen of radiation therapy aims to increase the dose in the target area while decreasing the dose in normal tissue. Radiotherapy for liver tumors has seen significant development in recent years. Despite the technological progress and improved accuracy of radiotherapy, the path of radiation reaching the target area still passes through normal tissues. Although there is tolerance doses as a reference parameter for normal liver exposure in planning, radiation damage still occurs. In addition, when combination of radiation therapy with chemotherapy, targeted therapy and immunotherapy has been widely used in recent years, the occurrence of RILD still affects the implementation of other treatment programs. In this review, latest research results of RILD are discussed to better understand the mechanism and provide research directions for optimizing radiotherapy.

Keywords: radiation-induced liver injury, radiation therapy, tolerance doses, normal tissue toxicity, radiotherapy optimization