[LOCALIZED AMYLOIDOSIS OF THE RENAL SINUS: A CASE REPORT].

An 80-year-old man was accidentally diagnosed with a left renal pelvic tumor by computed tomography (CT), and visited our hospital. A tumorous lesion with an inhomogeneous contrast effect occupying the left renal pelvis was confirmed by the contrast-enhanced CT scan, and enlargement of multiple lymph nodes around the aorta and inferior vena cava was recognized. Urine cytology of the left renal pelvis was pseudo-positive. In the preoperative diagnosis of left renal pelvic carcinoma cT3N2M0, left nephroureterectomy and lymph node dissection were performed. Pathological findings revealed an amyloid tumor confined to the renal sinus and diagnosed as localized amyloidosis.