International Journal of Urology (2006) 13, 1112–1114 Blackwell Publishing AsiaMelbourne, AustraliaIJUInternational Journal of Urology0919-81722006 Blackwell Publishing Asia Pty Ltd???200613811121114Case Report Primary renal angiosarcoma T Akkad et al. Corresponding: Thomas Akkad MD, Department of Urology, University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria. Email: thomas.akkad@uklibk.ac.at Received 20 January 2005; accepted 16 November 2005. Case Report Early diagnosis and straight forward surgery of an asymptomatic primary angiosarcoma of the kidney led to long-term survival THOMAS AKKAD, 1 ALEXANDAR TSANKOV, 2 ALEXANDRE PELZER, 1 REINHARD PESCHEL, 1 GEORG BARTSCH 1 AND HANNES STEINER 1 Departments of 1 Urology and 2 Pathology, Medical University Innsbruck, Innsbruck, Austria Abstract We report the first case of a diagnosis of an asymptomatic primary renal angiosarcoma. The patient underwent laparoscopic nephrectomy and is alive after long-term follow up. We provide the preoperative imaging studies and the histologic features of this exceedingly rare tumor. Key words angiosarcoma, kidney; neoplasm. Introduction Angiosarcomas are malignant vascular tumors which account for approximately 2% of all soft tissue sarcomas. They can occur in both sexes at any age and prevalently (60%) develop in skin or superficial soft tissue, mostly in the head and neck region or in the extremities. Visceral involvement, including the liver, thyroid, ovary, and other locations, is far less frequent. In some patients, angiosar- coma develops after radio therapy (RT) or in lymphedem- atous extremities after radical mastectomy without postoperative RT. Treatment of soft tissue sarcomas always involves radical surgery, as margin negativity is crucial for cure. Nevertheless, local recurrence develops in 20%-25% of cases despite seemingly adequate resection. 1 Regardless of the site, overall prognosis is quite poor due to early hematogenous dissemination, with metastases found commonly in the lungs, liver, and bone. Five-year survival rates of 10% to 35% have been reported. 1 Primary renal angiosarcoma is an extremely rare malig- nancy with poor prognosis due to usually advanced disease at time of diagnosis. We present the first case of an asymp- tomatic male patient with incidental finding of this tumor and describe the diagnostic and therapeutic procedures. A disease-free survival of 30 months is reported. Case presentation A 58 years-old man without history of flank pain, without hematuria or B-symptoms and with normal kidney func- tion underwent routinely performed ultrasound (US) and color Doppler US examination of the upper urinary tract. A relatively round shaped, peripherally hypervascular and centrally avascular tumor with a size of 4.5 cm × 4.0 cm was found in the lower pole of the right kidney (Fig. 1). Since the tumor did not show features of a simple cyst the diagnosis of a malignant tumor was made. Contrast- enhanced computed tomography (CT) confirmed the tumor, which demonstrated a rapid peripheral enhance- ment in the early arterial phase, which was higher (mean HU: 122) as compared with the renal cortex (mean HU: 107), and centrally no enhancement was found (Fig. 2). The wash-out of the contrast agent was faster in the tumor as compared with the renal parenchyma. Based on the CT findings a renal cell carcinoma or a cyst-associated renal cell carcinoma were suggested. Neither CT scan nor bone scan showed any other pathology. Laparoscopic nephrectomy was performed without delay; the patient was dismissed from hospital after 7 days. Pathohistologically, the tumor was built of polymorphic, medium-sized cells forming incomplete small vessels filled with blood and siderophages. The tumor cells infil- trated into neighboring blood vessels. Immunohistochem- ically, the tumor cells stained positively for the vascular markers CD-34 and factor VIII and remained negative for CD-10 and cytokeratin (Fig. 3). Furthermore, 25% of the tumor cells expressed flk-1 (vascular endothelial growth factor receptor 2) and 1% flt-1 (vascular endothelial growth factor receptor 1), as well as 5% the vascular endothelial factor (VEGF). The tumor cells remained negative for the hypoxia inducible factor-alpha (HIF-α). The final diagnosis was unilocular primary renal angiosarcoma; resection was complete (R0). No adjuvant treatment was performed. At a follow up of 30 months after surgery, the patient is free of recurrence. Discussion Primary renal angiosarcoma is extremely rare, with overall poor prognosis. Only two patients survived longer than 12 months. 2,3 Metastases at time of diagnosis are common 4,5 or develop within a few months or even weeks after surgery 3,6 due to early hematogenous dissemination,