Antipyrine metabolism and bronchogenic carcinoma.

Studies in animals indicate that tumor-bearing is associated with inhibition of hepatic drug metabolism. Our purpose was to determine the influence of a tumor on drug metabolism in man. The plasma clearance of antipyrine reflects the rate of its metabolism by the liver. Antipyrine clearance was measured in 7 patients with bronchogenic carcinoma and in 13 normal subjects and 7 patients with chronic lund disease. Mean (+/- SD) antipyrine clearance rates were 2.98 +/- 0.68 1/hr, 2.14 +/- 0.69 1/hr and 2.02 +/- 0.67 1/hr, respectively; indicating that bronchogenic carcinoma is associated with rapid, rather than slow, antipyrine metabolism. Antipyrine clearance (mean +/- SD) in 8 patients with bronchogenic carcinoma and evidence of liver metastases was 2.17 +/- 0.75 1/hr indicating that liver involvement by tumor decreased antipyrine clearance.