Case report: successful use of repotrectinib in a ROS1 fusion-positive lung adenocarcinoma patient with severe renal insufficiency and prior tyrosine kinase inhibitor treatment failure.

During sequential targeted therapy for ROS1 fusion-positive non-small cell lung cancer, some patients may develop severe renal insufficiency due to drug-related adverse events, resulting in limited subsequent treatment options with uncertain efficacy. We report a case of a 69-year-old female patient with advanced lung adenocarcinoma harboring an SDC4-ROS1 fusion mutation. Imaging revealed multiple nodules and masses in both lungs, enlarged mediastinal lymph nodes, and bilateral pleural effusion. The patient received treatment with crizotinib and entrectinib successively. During this period, the patient experienced renal hemorrhage and developed renal cysts and renal atrophy. Laboratory findings revealed persistently elevated serum creatinine levels and a significant decline in estimated glomerular filtration rate. She ultimately developed severe renal insufficiency, concurrent with tumor progression. Repotrectinib therapy was initiated based on tumor progression and renal function status under close monitoring, and an objective response occurred in this patient. Moreover, the serum creatinine levels decreased and remained relatively stable, indicating improved renal function. No new severe drug-related adverse events were observed. This case suggests that in patients with ROS1 fusion-positive nonsmall cell lung cancer who have experienced prior ROS1-tyrosine kinase inhibitor treatment failure and concomitant severe renal insufficiency, repotrectinib may represent a potential and tolerable treatment option when fully assessing clinical risks and ensuring close monitoring.