Renal cell carcinoma with hemorrhagic cyst formation in a 4-year-old boy.

We report on a case of renal cell carcinoma (RCC) with hemorrhagic cyst formation in a 4-year-old boy. The patient presented with asymptomatic macrohematuria. Abdominal ultrasound, computed tomography and magnetic resonance imaging demonstrated a left renal complicated cyst, 18 mm in diameter.