Surefire Infusion System vs. Standard Microcatheter Use During Holmium-166 Radioembolization

Study design: clinical within-subject randomized controlled trial. Study population: 25 patients with unresectable, chemorefractory, liver-dominant colorectal liver metastases. Intervention: scout and therapeutic doses of holmium-166 microspheres will be administered in the left and right hepatic artery during two sequential angiography procedures on the same day. In all subjects, the use of the Surefire Infusion System and the standard end-hole catheter will be randomly allocated to the infusion site (left and right hepatic artery). Baseline and follow-up investigation: at baseline and during follow-up, patients will undergo physical examination and laboratory investigations for toxicity assessment, and a whole-body 18F-FDG-PET + dual-phase liver CT (at baseline and 3-months follow-up) for tumor response assessment. After the scout procedure and therapeutic procedure, a holmium-166 SPECT/CT will be obtained for the assessment of the microsphere distribution. Main study parameters/endpoints: The primary endpoint is the tumor to non-tumor activity concentration ratio on SPECT/CT. Secondary endpoints include mean absorbed doses of radioactivity in tumorous and healthy liver tissue, tumor response, the predictive value of holmium-166 scout dose and infusion efficiency. These endpoints will be compared between the Surefire Infusion System and standard microcatheter infusions. A dose-response relationship, clinical toxicity and overall survival will be assessed for the entire cohort.