Stereotactic body radiation therapy for liver metastases in oligometastatic disease.

Oligometastatic cancers designate cancers in which the number of metastases is less than five, corresponding to a particular biological entity whose prognosis is situated between a localized and metastatic disease. The liver is one of the main sites of metastases. When patients are not suitable for surgery, stereotactic body radiotherapy provides high local control rate, although these data come mainly from retrospective studies, with no phase III study results. The need for a high therapeutic dose (biologically effective dose greater than 100Gy) while respecting the constraints on the organs at risk, and the management of respiratory movements require expertise and sufficient technical prerequisites. The emergence of new techniques such as MRI-guided radiotherapy could further increase the effectiveness of stereotactic radiotherapy of liver metastases, and thus improve the prognosis of these oligometastatic cancers.