Sunitinib-induced nephrotic syndrome and irreversible renal dysfunction

Area of Science:

• Nephrology
• Oncology
• Pharmacology

Background:

• Sunitinib, a tyrosine kinase inhibitor targeting vascular endothelial growth factor receptors (VEGFRs), is crucial for imatinib-resistant gastrointestinal stromal tumors.
• Anti-VEGF therapies, including sunitinib, have been linked to proteinuria and kidney dysfunction, though reversibility is not fully understood.

Observation:

• A 72-year-old man developed nephrotic syndrome and renal dysfunction six months after starting sunitinib.
• Discontinuation of sunitinib led to spontaneous remission of nephrotic syndrome, but limited renal function recovery.

Findings:

• Renal biopsy revealed endothelial cell injury, focal segmental glomerulosclerosis, and increased VEGF expression by podocytes.
• The case suggests long-term, high-dose sunitinib can cause irreversible renal damage.

Implications:

• Kidney dysfunction and nephrotic syndrome are rare but serious sunitinib complications.
• Reduced sunitinib dosage may help manage these renal side effects, potentially allowing continued treatment.