Renal Angiomyolipoma Associated with Rapid Enlargment and Inferior Vena Caval Tumor Thrombus

A 56-year-old woman presented 2 years after diagnosis of a right renal mass consistent with angiomyolipoma. The patient had a history of breast cancer treated by surgery and radiotherapy 10 years previously. She had no personal or family history of neurological disease or phakomatoses. Nine years before presentation, as part of breast cancer followup, abdominal computerized tomography (CT) showed absence of renal lesion. Two years before presentation the patient complained of right flank pain and CT reveale da3c mfatty tumor. The diagnosis of angiomyolipoma was established. Because of the small tumor size and the spontaneous improvement of symptoms, watchful waiting was planned with alternate ultrasound and CT annually or every other year. Two years later the patient had pain recurrence and CT demonstrated a 4.5 cm fatty mass of the right renal sinus with a tumor thrombus extending into the right renal vein and IVC. Physical examination was unremarkable and routine laboratory data were normal. Magnetic resonance imaging confirmed a sinusal right renal mass extending into the right renal vein and IVC 2 cm under the hepatic veins (fig. 1). Right nephrectomy and thrombectomy with a short cavotomy were performed. Pathological analysis showed renal angiomyolipoma with an 8 cm fatty thrombus (fig. 2). The patient was discharged home on postoperative day 9. She remained asymptomatic without evidence of recurrent disease at 1 year postoperatively.