Radioembolization with infusion of yttrium-90 microspheres into a right inferior phrenic artery with hepatic tumor supply is feasible and safe.

To evaluate the feasibility and safety of yttrium-90 ((90)Y) radioembolization through the inferior phrenic arteries (IPAs).Retrospective analysis of 108 patients referred for radioembolization to treat primary (n = 103) or secondary (n = 5) liver malignancy was performed. Five patients had malignant hepatic tumors supplied by the IPA and met criteria for infusion of (90)Y spheres into the IPA. Digital subtraction angiography (DSA), catheter-directed computed tomographic (CT) angiography, and technetium-99m ((99m)Tc) macroaggregated albumin (MAA) single photon emission CT (SPECT)/CT were used to plan treatment. Bremsstrahlung SPECT/CT was performed 1 day after radioembolization. Follow-up included clinical and biochemical tests and cross-sectional CT or magnetic resonance imaging.Parasitized extrahepatic arteries were detected in 37% of patients (n = 40). Of these, 62.5% (n = 25) had tumor supply through an IPA. Of the patients with IPA supply, 20% (n = 5) underwent infusion of (90)Y into the right IPA. Reasons for disqualifying patients from infusion into the IPA were less than 10% tumor supply (n = 11), failed catheterization of IPA (n = 3), arterioportovenous shunt (n = 2), failed identification of IPA on pretreatment angiography (n = 1), and gastric or esophageal enhancement on catheter-directed CT angiography (n = 3). In all five patients, technical success was demonstrated on (90)Y imaging, with no significant extrahepatic radionuclide activity. No adverse events related to IPA radioembolization occurred at mean follow-up of 4.5 months (range, 2.2-10.1 mo).Delivery of (90)Y microspheres through the right IPA is feasible and safe with the use of catheter-directed CT angiography in addition to DSA and (99m)Tc MAA SPECT/CT in patients with tumors with greater than 10% IPA supply.