Case Report: Abemaciclib-Induced Chronic Renal Failure

Abemaciclib, a cyclin-dependent kinase 4/6 inhibitor, may induce kidney damage during the treatment of hormone receptor-positive/human epidermal growth factor receptor 2-negative breast cancer. We report a case of a 52-year-old woman with normal baseline kidney function (serum creatinine, 68.19 μmol/L; eGFR, 89 mL/(min·1.73 m²); blood urea nitrogen, 7.74 mmol/L; cystatin C, 0.74 mg/L) who developed stage 2 chronic kidney disease after 12 months of abemaciclib therapy (150 mg/day, twice daily). Three months after discontinuation, kidney function recovered (serum creatinine, 73.80 μmol/L; normalized cystatin C and uric acid), but creatinine rose again to 92.5 μmol/L within 1 month of reinitiation. This case suggests that long-term abemaciclib use may lead to kidney damage, potentially progressing to chronic kidney failure. Regular monitoring of renal function indicators is recommended before and during treatment.