RENAL ANGIOMYOLIPOMA IN CHILDREN - DIAGNOSTIC DIFFICULTY IN 3 PATIENTS

Purpose: Because angiomyolipoma is less common in children than in adu lts, its diagnosis can be difficult. We present 3 cases of pediatric a ngiomyolipoma in which diagnostic problems resulted due to the present ing characteristics. Materials and Methods: We report on 3 children wi th unilateral renal angiomyolipoma. Computerized tomography (CT) and u ltrasonography revealed 3 large renal masses, 20, 7 and 8 cm. in diame ter, respectively. A correct diagnosis was not made preoperatively in any case by CT, ultrasound or fine needle biopsy. Wilms tumor was susp ected in the first patient who received preoperative chemotherapy. Ima ging was inconclusive in the other 2 cases. Results: All patients unde rwent surgical exploration and subsequent nephrectomy due to the large size of the tumor. At followup 33, 23 and 13 months postoperatively a ll children were well without signs of recurrence. Conclusions: It has been reported that the demonstration of fat on renal ultrasound and C T can diagnose angiomyolipoma in 95% of the cases. Most radiologists r ely solely on CT demonstration of lipid density in the renal mass to d iagnose angiomyolipoma but the identification at imaging of lipid tiss ue may be difficult in small tumors. In our cases the fat content of t he tumors was less than 10% despite the large size. This low fat conte nt results in misdiagnosis, since fatty tissue is also present in othe r renal tumors, such as lipoma, liposarcoma, teratoma and Wilms tumors . We recommend conservative surgery when tumor size permits in pediatr ic patients with angiomyolipoma to avoid chemotherapy.