Development of Renal Cysts after Crizotinib Treatment in Advanced ALK-Positive Non–Small-Cell Lung Cancer

IntroductionThe development of complex renal cysts after crizotinib treatment for non–small-cell lung cancer (NSCLC) is a reported side effect. However, its occurrence and characteristics have not been reported.MethodsMedical records and computed tomography images of crizotinib-treated patients in three prospective clinical trials were reviewed. The size and Bosniak category of the renal cysts before and after crizotinib treatment were determined. Patients’ clinical characteristics, tumor stage, treatment response, renal function, and outcomes were analyzed.ResultsDuring December 2010 to March 2013, we enrolled 32 patients who received crizotinib. There were 23 patients who had renal cysts before crizotinib. The median follow-up time was 493 days. Seven patients (22%, six with baseline renal cyst and one without baseline renal cyst) had significant renal cyst change. Four (13% of all) had new complex renal cysts. The median time from crizotinib treatment to first recognization of significant renal cyst change was 77 days. After stopping crizotinib, complex renal cysts regressed significantly. Patients with significant renal cyst change received more previous anticancer therapy (median, 5 lines versus 3 lines, p = 0.04) and received crizotinib for longer duration (median, 956 days versus 248 days, p = 0.007) compared with those without significant renal cyst change.ConclusionsChange of renal cysts after crizotinib treatment is not uncommon. Development of complex renal cysts reverses after stopping crizotinib.