Testing the Addition of Total Ablative Therapy to Usual Systemic Therapy Treatment for Limited Metastatic Colorectal Cancer, ERASur Trial

This phase III trial compares the addition of total ablative therapy to the usual systemic therapy versus the usual systemic therapy alone in treating patients with advanced colorectal cancer that has spread to up to 4 body sites (limited metastatic). The usual approach for patients who are not participating in a study is treatment with intravenous (through a vein) and/or oral medications (systemic therapy) to help stop the cancer sites from getting larger and the spread of the cancer to additional body sites. The ablative local therapy will consist of any combination of very focused, intensive radiotherapy called stereotactic ablative radiotherapy (SABR), surgical resection, or microwave ablation, which is a procedure where a needle is temporarily inserted in the tumor and heat is used to destroy the cancer cells. The addition of ablative local therapy to the usual approach of systemic therapy could be more effective than usual chemotherapy alone by increasing the life of patients with limited metastatic colorectal cancer.