Radioembolization for CRC Liver Metastases

Radioembolization is a commonly used modalities for the treatment of patients with advanced liver metastases from colorectal cancer (CRC), particularly those that fail to respond to chemotherapy. Selective internal radiation therapy (SIRT) is a newer form of radioembolization that uses resin microspheres that emit Yttrium-90 to portions of the liver or the whole liver, explains Marwan Fakih, MD. The radiation is emitted to a small area for a period of approximately 2 weeks via catheterization through the groin and hepatic artery.

Radioembolization with resin microspheres is an outpatient procedure that is well tolerated, comments Fakih. The procedure is not associated with any major toxicity, although mild nausea and fatigue are sometimes reported. SIRT is typically reserved for individuals with liver-predominant disease that is unresectable, states Fakih. It has been associated with improvement in progression-free survival (PFS) in both first-line and second-line disease settings. In the phase III SIRFLOX trial, adding SIRT to frontline FOLFOX-based chemotherapy improved liver-specific PFS by 7.9 months for patients with liver-dominant CRC metastases. Additionally, this procedure could downstage the disease, Fakih notes.

There are less data available supporting the use of chemoembolization, or drug eluting beads, for patients with liver metastases, says Fakih. Drug eluting beads may result in more toxicity than SIRT. Oftentimes, patients are readmitted to the hospital after the procedure, and the procedure may need to be repeated to achieve the best outcome. At this time, head-to-head studies between drug eluting beads and SIRT have not been conducted, notes Fakih.