Multiple Arteries Supplying a Single Tumor Vascular Distribution: Microsphere Administration Options for the Interventional Radiologist Performing Radioembolization

Radioembolization (RE) has become an increasingly common procedure for patients with liver-dominant primary liver tumors or metastatic disease. Results for RE are generally considered to be as favorable as transarterial chemoembolization (TACE), and may even be more beneficial than TACE in certain clinical settings. The choice of RE versus TACE still largely remains one of operator, patient, and referring provider's preference, and there are clear institutional biases for one treatment over the other. It is the authors' opinion that both procedures should be offered by interventional radiology departments, to allow the greatest latitude in the treatment of patients with liver-dominant malignancies.

Until one becomes facile with RE as a procedure, it can seem more technically challenging to perform compared with TACE. The technical administration of the agent is not the difficult part of the procedure; interventional radiologists (IRs) are experts at placing catheters where they need to be, and administering embolic agents of all sorts into arteries supplying any organ in the body. The difficulties with RE arise more from the technical specifics due to administering highly radioactive particles themselves, and occur due to the great need to protect both the patient and the operating staff from unintentional administration of radioactivity. The particular steps in the process that distinguish RE from TACE include dosimetry calculations, embolization of extrahepatic collaterals, and the inability to freely move a catheter through which radioactive particles have already been injected. It is the latter issue that is the topic of this article.

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