MEASURING LUNG SHUNTING IN HEPATOCELLULAR-CARCINOMA WITH INTRAHEPATIC-ARTERIAL TC-99M MACROAGGREGATED ALBUMIN

With increased use of intraarterial administration of chemotherapeutic and radioactive particulate agents, it is necessary to assess agent delivery in the lung. Methods: Technetium-99m-labeled macroaggregated albumin (Tc-99m-MAA) delivered through the hepatic artery was used to determine the degree of lung shunting in 125 patients with hepatocellular carcinoma (HCC). Results: The percentage of lung shunting varied among patients and it ranged from less than 1% to 67.2%, with a median of 8.1%. The degree of shunting depended on the vascularity of the tumors but not on the tumor size. The effect of angiotensin II on lung shunting was tested on six patients and there was no significant difference found between those patients who were pre-treated with angiotensin II and those who were not. One patient who underwent a liver resection, had a significant decrease in lung shunting from 28.5% to less than 1% after surgery. Conclusion: The lack of effect of angiotensin II together with the almost complete ablation of lung shunting by tumor resection suggested neoplastic blood vessels were responsible for the shunting.