Non-interventional Observational Study of Helical Tomotherapy for Oligometastatic Colorectal Cancer

Patients with oligometastatic colorectal cancer (5 metastases or less) receive a combination of systemic treatment and often local treatment, such as surgery, radiofrequency ablation and more recently stereotactic body radiotherapy. The aim of this study is to register the results and side effects of stereotactic body radiotherapy (SBRT) by means of helical tomotherapy in the treatment of oligometastatic colorectal cancer.
The trial has two cohorts. Patients in cohort I get consolidation SBRT after best response on first line chemotherapy. Patients in cohort II get SBRT when there is progression under, or no indication for (further) chemotherapy. The primary endpoint is to evaluate the metabolic complete remission rate three months after the start of radiotherapy.