Irreversible pulmonary toxicity after single course of BCNU.

Irreversible pulmonary interstitial fibrosis developed 36 days after a single course of BCNU (total, 400 mg) in a patient with a malignant brain tumor. The case is unique in that irreversible changes developed shortly after a single course of BCNU whereas heretofore such permanent changes have been associated only with multiple courses of the drug (2,000-4,000 mg). This suggests that individual differences in the local sensitivity of lung tissue may be as important as the dose of the drug in determining whether irreversible fibrosis will develop.