Feng M, et al. - The safety and efficacy of individualized adaptive stereotactic body radiotherapy (SRBT) for liver tumors in patients who have preexisting liver dysfunction have been described. Findings exhibited that the treatment strategy of individualized adaptive therapy based on a direct biomarker of liver function could have utility in achieving both high rates of local control and a high degree of safety without sacrificing either. Individualized adaptive radiotherapy, in which dose is based on individual, rather than population-based, tolerance to treatment, could serve as a new treatment paradigm.