Abstract

The concept of metastatic disease has evolved and therapeutic approaches have changed. The concept of oligometastatic disorder emerged over the past decade with the intention to develop curable treatment. Oligometastatic disease represents a condition between absence of metastases and widespread dissemination with a maximum of five metastatic sites. The most commonly used therapeutic approach for treatment of oligometastases is surgery. However, in colorectal cancer only 20% of patients with liver oligometastases are eligible for surgery. In recent years stereotactic body radiation therapy (SBRT) or stereotactic ablative radiation therapy (SABR) has been used for many primary and secondary tumours, including oligometastases, with promising results. Many retro- and prospective studies have demonstrated efficacy in terms of tumour control and, in a limited subset of patients, also survival (lung, liver, bone, lumbal and brain oligometastases). The adverse effects of SBRT/SABR are acceptable, being in most cases mild or moderate. Local control in most studies varies between 70-95% depending on the tumour site. SBRT/SABR has changed the role of radiation therapy for metastatic disease, which has evolved from palliation of symptoms to a potentially curative intent. Since there are no randomised controlled trials directly comparing SBRT/SABR with surgery, the role of SBRT/SABR is not finally defined. Randomised studies are required to confirm clinical evidence and long term results.