Abstract
Aminopyrine metabolism was assessed by the aminopyrine breath test (ABT) in 153 patients with malignant disease, 75 of whom had hepatic neoplasms and 78 had none. Radioactive 14CO2 exhalation was measured 2 h after oral administration of a trace dose of 14C-aminopyrine. The ABT was correct in 62 of 75 (83%) patients with hepatic neoplasms and 73 of 78 (94%) patients without. It was correct in 16 of 22(73%) patients who had hepatic neoplasms without abnormal serum biocehmistry. Aminopyrine metabolic clearance rate (AMCR) was 32.4 ml/min in patients with hepatic neoplasm and 103.4 .+-. 18.8 ml/min in patients without. There was a significant correlation between ABT and AMCR (r = .76, P < .01). Aminopyrine metabolism is depressed in most patients with hepatic neoplasms, and the ABT affords a useful method for detecting malignant tumors of the liver.