Nephrotoxicity of nitrosoureas

Area of Science:

• Nephrology
• Oncology
• Pharmacology

Background:

• Malignant brain tumors require aggressive treatment.
• Nitrosoureas are a class of chemotherapy drugs used in cancer therapy.
• Potential long-term side effects of chemotherapy require careful monitoring.

Purpose of the Study:

• To investigate the incidence and nature of renal damage in patients treated with nitrosoureas for malignant brain tumors.
• To assess the relationship between the cumulative dose of nitrosoureas and the development of nephrotoxicity.

Main Methods:

• Retrospective analysis of patient data, including treatment regimens and renal function tests.
• Evaluation of renal function using blood urea nitrogen, serum creatinine, and inulin clearance.
• Histopathological examination of renal tissue from affected patients.

Main Results:

• A high incidence of irreversible renal parenchymal damage and functional impairment was observed in patients receiving six or more courses of nitrosoureas (BCNU and/or methyl CCNU).
• Impaired renal function, indicated by elevated blood urea nitrogen/serum creatinine or decreased inulin clearance, occurred in 17 of 18 patients with ≥6 courses and all 9 patients with >10 courses.
• Renal biopsy findings included tubular atrophy, interstitial fibrosis, and glomerular sclerosis, consistent with a progressive interstitial renal lesion, often without preceding acute renal failure or significant urinary abnormalities.

Conclusions:

• Nitrosourea-based chemotherapy for malignant brain tumors is associated with a high risk of progressive and irreversible nephrotoxicity.
• The observed renal damage is characterized by interstitial fibrosis and tubular atrophy, developing insidiously.
• Close monitoring of renal function is crucial for patients undergoing long-term nitrosourea treatment.