MITOMYCIN LUNG TOXICITY - ACUTE AND CHRONIC PHASES

Pulmonary toxicity is a rare but well described side effect of mitomyc in C (MMC). We describe 14 cases of MMC pulmonary toxicity that were d etected in four clinical trials performed at The Mayo Clinic using MMC -containing regimens for nonsmall cell lung cancer (NSCLC) and by revi ewing the charts of patients treated at The Mayo Clinic with MMC-conta ining regimens for NSCLC from 1976 to 1995. The median age was 61 (ran ge 44-84) years, with an M:F ratio of 1:1. The median number of cycles of MMC to develop toxicity was four (range two to five) with a median cumulative dose of MMC of 29 mg/m(2). MMC toxicity occurred despite p re-medication with corticosteroids in 11 patients. At diagnosis of MMC lung toxicity, the median diffusing lung capacity (DLCO) was 9 and-Pa O2 was 49 mm Hg. Of those having bronchoscopy, four patients had pulmo nary histologic changes consistent with lung injury. Two patients had bronchioalveolar lavages that were nondiagnostic. All patients respond ed initially to corticosteroids, but approximately 40% had progressive pulmonary insufficiency despite high doses of corticosteroids. This c hronic, progressive phase of MMC lung toxicity is a largely underestim ated sequelae of MMC.