A 70-year-old woman had a past history of hypertension and atrial fibrillation. She was found to have bladder cancer, hydronephrosis, and mild renal failure because of intermittent painless gross hematuria. She received transurethral resection of bladder tumor, double J stent insertion, and mitomycin intravesical chemotherapy. However, she developed edema and progressive renal failure of unknown cause. She was admitted for further examinations.