Retroperitoneal cellular schwannoma

We present the case of a female patient, 35 years old, who had a complaint of sporadic left flank pain for 5 years. She said she had no comorbidities. The results of the laboratory tests did not show abnormalities. Previous ultrasonography of the urinary tract (without the use of color Doppler) described a possible single cyst postero-inferiorly to the left renal pelvis. In recent ultrasound we observed that topography massive oval formation markedly hypoechoic with discrete intermingled flow. Subsequent abdominal computed tomography and magnetic resonance imaging characterized retroperitoneal mass along the hilum of the left kidney, associated with renal dimensional reduction and ipsilateral hydronephrosis. Histological diagnosis after tumor excision: cell schwannoma (Antoni A histological standard only).