Entrectinib-induced tubulointerstitial nephritis: a case report

Entrectinib has been approved and increasingly administered for the treatment of non-small cell lung cancer, especially with intracranial metastasis. Although previous clinical studies have confirmed its safety, disproportionality analysis showed unusually high potential adverse renal effects. We present a case of a 71-year-old woman with pulmonary adenocarcinoma who developed severe renal function impairment during the treatment with entrectinib. Urinary sediment examination revealed leukocyte casts, while urinary culture was negative, suggesting the presence of possible tubulointerstitial nephritis (TIN). A kidney biopsy was performed, and the diagnosis of TIN was confirmed. The administration of oral methylprednisolone improved renal function. Protein kinase inhibitors might lead to renal function impairment in several different ways. It is of utmost importance to differentiate between the underlying pathomechanism, which is often challenging. TIN is a potentially reversible condition when treated appropriately. In the case of renal function impairment during entrectinib therapy, the possibility of TIN should be considered, and a kidney biopsy should be performed since corticosteroid therapy might improve renal function.