Management of renal angiomyolipoma: a report of 53 cases


Dr Terrone Clinica Urologica dell’Università di Torino, A.M. Dogliotti 14, 10126, Torino, Italy.



To evaluate the clinical, therapeutic and prognostic aspects of renal angiomyolipoma (AML) in patients either monitored by clinical and radiological follow-up or treated by surgical therapy.

Patients and methods

Fifty-three patients with renal AML were divided in two groups; 33 patients in group 1 were monitored by annual clinical and ultrasonographic follow-up and 20 in group 2 were treated with surgical therapy. Two patients had tuberous sclerosis (TS) with synchronous bilateral and multiple lesions. Apart from the patients with TS, there were 38 lesions in group 1 and 25 in group 2. The mean (range) follow-up of group 1 was 60.2 (12–164) months.


In group 1, the diagnosis was most often incidental, after ultrasonography performed for symptoms unrelated to AML. In group 2, the suspicion of a malignant renal lesion, and spontaneous tumour rupture with bleeding and perirenal haematoma, were the main indications for surgical treatment. The mean lesion diameter was significantly greater in group 2 (5.4 cm) and in symptomatic patients (8.1 cm). In group 1, 92% of renal AMLs showed no radiographic changes, serious complications or new renal or extrarenal lesions during the follow-up. Only three lesions grew, after 22, 85 and 164 months, respectively. Of the 20 patients in group 2, 14 underwent conservative surgery.


Small (<4 cm) isolated AMLs, detected incidentally, showed a low risk of developing during long-term follow-up. Such patients may be followed conservatively by ultrasonography every 2 years. Spontaneous perinephric haemorrhage is related to the size of the lesion. When surgery is indicated (by symptoms or diagnostic doubt), a conservative procedure can be performed in most of cases.