DRAGON 2 - An international multicenter randomized controlled trial to compare combined Portal and Hepatic Vein Embolization (PVE/HVE) with PVE alone in liver surgery

Patients who suffer from colorectal cancer that has spread to the liver (metastases) can be treated with liver surgery. Liver surgery is the most effective treatment in improving survival for this disease, and up to 30% of patients can be cured. Liver surgeons can safely remove up to 70% of the liver. Unfortunately, for some patients, removal of all tumors will leave a remnant liver that is smaller than 30%, placing patients at risk for life-threatening liver failure after surgery. To prevent this, a procedure can be performed to let the liver grow prior to surgery. This "portal vein embolization" (PVE) is performed 6 weeks prior to surgery. During this time, it is possible for the cancer to grow or for the liver to grow insufficiently, such that surgery becomes impossible or unsafe. Surgeons have begun using a variation of PVE, which involves concurrently blocking other liver veins ("hepatic vein embolization", HVE). In preliminary research, combined PVE/HVE has been safe and highly effective at inducing rapid and profound growth of the liver. Acceleration of liver growth can bring more patients to surgical resection of their cancer, resulting in increased chances of survival and cure. The DRAGON-2 study is an international clinical trial. Its objective is to compare the two liver growth interventions prior to surgery for colorectal cancer metastases. The main outcomes under study will be whether the liver reaches sufficient growth to allow for resection at 3 weeks, as well as patient survival for up to five years after surgery. Several hospitals around the world will be participating in this trial, including 14 Canadian sites. This application seeks funding for the Canadian sites, and for the trial's economic analysis. Altogether, DRAGON-2 will enrol 348 patients, of which 100 will come from Canada. This trial will be the largest in the field and will provide definitive evidence regarding the value of dual embolization procedures prior to liver surgery.