ROLE OF SINGLE-BREATH CARBON MONOXIDE-DIFFUSING CAPACITY IN MONITORING THE PULMONARY EFFECTS OF BLEOMYCIN IN GERM-CELL TUMOR PATIENTS

Abstract

Serial pulmonary function tests including single-breath carbon monoxide-diffusing capacity (DLCO), forced vital capacity (FCC), and forced expiratory volume in 1 s were performed in a relatively homogeneous group of male patients with germ cell tumors treated with vinblastine, bleomycin and cis-diamminedichloroplatinum. The DLCO was the most sensitive indicator of subclinical bleomycin pulmonary effects. Decreases in DLCO were total dose and schedule dependent. Patients receiving their total dose of bleomycin at a rate of 25 .+-. 2 (SD) units/wk developed a linear decrease in DLCO with increasing total doses of bleomycin. Changes in FVC did not correlate with bleomycin total dose. Although the mean DLCO and FVC decreased after completion of bleomycin therapy, the mean FVC returned to base-line levels rapidly, whereas the decrease in mean DLCO was persistent for several months. When routine volumetric tests (FVC and forced expiratory volume in 1 s) and DLCO are used in a systematic manner, DLCO is the most sensitive indicator of the subclinical pulmonary effects of bleomycin in germ cell tumor patients treated with vinblastine, bleomycin and cis-diamminedichloroplatinum.