[Renal Pelvic Cancer with Delayed Diagnosis Due to Left Renal Injury : A Case Report].

We report a case of renal pelvic cancer found after left renal trauma. A 63-year-old man was admitted to our hospital because of gross hematuria after he had fallen down the stairs two days earlier. He had asymptomatic severe anemia (Hb : 3. 6 g/dl). Abdominal computed tomography (CT) scan revealed bilateral ureteropelvic stones, bilateral severe hydronephrosis and hematoma of the left upper renal pelvis. We diagnosed him with left renal pelvic hemorrhage by trauma, and transcatheter arterial embolization (TAE) was performed. After TAE, gross hematuria improved, but some hematuria continued to be noted. We suspected malignancy, and examined the patient with contrast-enhanced CT, transurethral resection and retrograde pyelography combined with urine cytology in the upper urinary tract, all with no evidence of malignancy. However, four months after the left renal injury, follow-up CT revealed multiple metastatic lesions. We performed a left nephrectomy, and the resulting pathological diagnosis was invasive urothelial carcinoma with squamous differentiation of the renal pelvis. We performed 7 courses of chemotherapy, but the multiple metastatic lesions progressed, and he died of the disease 19 months after the operation.