Purpose: Intra-arterial injection of Yttrium-90 glass microspheres ((90)Y- microS; TheraSphere, MDS Nordion, Ottawa, Canada) is indicated for treatment of unresectable hepatocellular carcinoma (HCC) in the presence of acceptable liver function. This study presents hepatic toxicity results after unilobar and bilobar intra-arterial administration of (90)Y- microS in patients with unresectable HCC who had known portal vein thrombosis (PVT) without evidence of cavernous transformation.
Materials and methods: Fifteen patients with unresectable HCC and PVT of one or both first order and related segmental portal venous branches received a total of 29 infusions of (90)Y- microS for treatment of HCC. All patients had pretreatment evaluation including: computed tomography (CT) imaging, alpha-fetoprotein (AFP) levels, liver function tests, technetium-99m macroaggregated albumin ((99)Tc-MAA) scan for evaluation of lung and visceral shunting, and angiography with visualization into the portal venous phase. (90)Y- micro S dose was based on lobar hepatic volume with adjustment for lung shunt activity. Liver toxicity was assessed by serum total bilirubin graded for severity according to the NIH NCI Clinical Toxicity Criteria (CTC version 2.0). Other adverse events were reported according to the standards established by the Society of Interventional Radiology.
Results: There were no procedural complications with delivery of (90)Y- microS, and treatment was well tolerated by all patients. Increased post-treatment bilirubin levels were observed across all treatments in five patients, four of whom had CT or AFP evidence of intrahepatic disease progression. After initial treatment, two patients developed bilirubin toxicity (grades 1 and 2); one patient demonstrated an increment in bilirubin toxicity grade (grade 1 to grade 3) and one patient had an improvement in grade after initial treatment. There were no new treatment-related toxicities in nine patients after a second treatment.
Conclusions: (90)Y- microS treatment was well tolerated and appears to be safe to use in patients with compromised portal venous flow in one or both first order and related segmental portal venous branches and no evidence of cavernous transformation. In patients who did not exhibit disease progression, there appeared to be no clinically significant change in bilirubin.