Nephrotoxicity of nitrosoureas.

Irreversible and progressive renal parenchymal damage and functional impairment occurred in the majority of patients receiving at least six courses (200 mg/m2 of BCNU and/or methyl CCNU at eight-week intervals) of nitrosoureas for therapy of malignant brain tumors. Seventeen of 18 patients who received at least six courses and all nine patients who received more than ten courses developed impaired renal function as judged by elevation of blood urea nitrogen and/or serum creatinine or decrease in filtration rate as determined by inulin clearance. Four patients have developed uremia. Renal tissue obtained from seven patients demonstrated tubular atrophy, interstitial fibrosis and glomerular sclerosis. This remarkably high incidence of renal damage occurred without a phase of acute renal failure and in the absence of significant urinary abnormalities, while producing an insidiously progressive interstitial renal lesion.