Minimal change nephrotic syndrome associated with gefitinib and a successful switch to erlotinib.

Minimal change nephrotic syndrome (MCNS) is a common form of nephrotic syndrome (NS). We herein present the case of a 57-year-old woman with advanced lung adenocarcinoma treated with the tyrosine kinase inhibitor (TKI) gefitinib who developed NS. A renal biopsy revealed minor glomerular abnormalities, and the patient's symptoms improved exclusively with the discontinuation of gefitinib. Therefore, we diagnosed her with MCNS associated with gefitinib treatment. A few months later, however, she developed recurrent lung tumors. Following the challenging initiation of the TKI erlotinib, she achieved remission without proteinuria. We thus conclude that erlotinib is a potential treatment option in patients with NS associated with gefitinib therapy.