AUA 2017: Big Renal Angiomyolipoma: The 4 cm size limit for conservative management should be revisited?

Boston, MA ( Recent publications have challenged the previous dogma that is unsafe to follow AML > 4 cm in size. Previous reports stated the risk of bleeding rose proportionally with AML size and the likelihood of a successful nephron-sparing procedure was less likely in larger masses. Sadly, there are a significant number of patients in whom intervention may not be advised due preexisting renal dysfunction or bilateral disease as in the case with tuberous sclerosis patients. Professor Gomha, from the Urology Institute in Mansura presents his experience with the conservative management of patients with AMLs ≥ 10 cm in size.

To date Dr. Gomha as followed 11 patients with AMLs > 10 cm in size. Most of the patients were diagnosed incidentally with only 1 patient presenting with pain related to 16 cm lesion. Six patients presented with bilateral disease, five of them having tuberous sclerosis. The median mass diameter was 15.5 cm with a range of 10-32 cm. Large intra-renal aneurysm (≥ 10mm) were detected in 3 renal units, all of which underwent selective embolization. The majority of AML’s had predominant fat content with only 3 having a predominant angiomyomatous component. Conservative management was successful in 7 of the 11 patients. Patients were followed with serial imaging Q6months for 2 years then annually thereafter. At a median follow-up of 68 months, all patients remained asymptomatic and with stable renal function. Most AMLs remained stable in size with only two showing very slow growth (1-2mm/year).

Two patients underwent partial nephrectomy, one for pain and the other due to concern that the AML could represent a liposarcoma. Everolimus therapy was given to 4 patients, but only 1 had a clinically significant response.

In conclusion, large AMLs, even those ≥ 10 cm, can be managed conservatively. Most of this large AMLs remain asymptomatic and have low potential for bleeding if the large aneurysm are treated preemptively. Renal function remained stable over time, which debunks the prior misconception, that large masses may affect renal filtration.

Presented By: Mohamed A. Gomha, Urology Institute of Mansura, Egypt

Written By: Andres F. Correa, MD, Society of Urologic Oncology Fellow, Fox Chase Cancer Center, Philadelphia, PA

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA