G. timac et al. A rare case of renal cell carcinoma in a patient with crossed-fused ectopia Acta clin Croat, Vol. 43, No. 3, 2004 !# Acta Clin Croat 2002; 43:305- Case Report A RARE CASE OF RENAL CELL CARCINOMA IN A PATIENT WITH CROSSED-FUSED ECTOPIA: SURGICAL AND RADIOLOGIC CONSIDERATIONS Goran timac 1 , Borislav Spajiæ 1 , Boris Ruiæ 1 , Josip Katuiæ 1 , Mario Suèiæ 1 , Ratimira Klariæ-Èustoviæ 2 , Ognjen Kraus 1 1 Clinical Department of Urology, Sestre milosrdnice University Hospital, Zagreb, Croatia 2 University Department of Diagnostic and International Radiology, Sestre milosrdnice University Hospital, Zagreb, Croatia SUMMARY  Crossed-fused renal ectopia is an uncommon condition and cases of malignant tumors in such anomalies are extremely rare. A case of renal cell carcinoma in a patient with crossed-fused ectopia is reported. The patient was successfully treated with partial nephrectomy following isthmus division. Radio- logic investigations and operative findings are presented. It is thought to be the fourth reported case of renal cell carcinoma in crossed-fused ectopia. Key words: Carcinoma renal cell  diagnosis; Carcinoma renal cell  surgery; Kidney  abnormalities; Kidney neoplasms  pathology Correspondence to: Goran timac, M.D., Ulica Svetog Mateja 121, HR- 10000 Zagreb, Croatia E-mail: goran.stimac2@zg.htnet.hr Received April 26, 2004, accepted June 28, 2004 Introduction A case of renal cell carcinoma (RCC) in a man with crossed-fused renal ectopia is reported. It is an uncommon congenital anomaly and cases of malignant tumors in such conditions are extremely rare. Radiologic studies suggest- ed a hypervascular tumor on the upper pole of the crossed kidney next to the fusion line. Radical nephrectomy with isthmus division was performed successfully. The value of thorough urologic and radiologic investigations is stressed. To our knowledge, this is the fourth case report of this rare condition. Case Report We report on a case of RCC in a 62-year-old man who was previously diagnosed for 20 years with left-to-right crossed-fused renal ectopia. The patient was assessed for persistent right abdominal and lumbar pain. There was no hematuria. Laboratory evaluation was normal. IVP, CT and MRI showed a 6-cm parenchymal mass on the superior and lateral aspect of the left lower crossed kidney close to the line of fusion (Fig. 1). Angiography was performed to decide on definitive treatment and to establish the extent of tumor (Fig. 2). It was essential to show us which kid- ney the tumor originated from. Vascular anatomy of the crossed kidney comprised a single renal artery from the left common iliac artery and a single renal vein draining into the left common iliac vein. The drainage of the tumor orig- inated from the left kidney. The patient underwent trans- abdominal radical nephrectomy with isthmus division of the left crossed kidney, along with tumor resection through the right pararectal incision. There was no lymph node involvement. Pathologic specimen revealed a 6-cm RCC of the upper pole of the left kidney, T1NoMx, Fuhrmann grade III, of clear cell type without invasion of the capsule or renal pelvis. The tumor did not extend to the resection margin of the fused kidneys. At two years postoperatively, the patient was well, and there were no tumor masses or enlarged lymh nodes on control abdominal CT scan. Discussion Crossed renal ectopia is an uncommon congenital anomaly and in most of the cases it usually presents with