Angiomyolipoma managed by partial nephrectomy: Outcomes and follow-up

Abstract

Angiomyolipoma (AML) is a benign neoplasm and consists of thick-walled poorly organized blood vessels, smooth muscle, and varying levels of mature adipose tissue. We evaluated the impact of clinical characteristics, particularly tumor diameter, and surgical treatment in the form of partial nephrectomy on the outcome of sporadic renal AML. Patients undergoing partial nephrectomy during the period Jan 2000 to Dec 2016 with a final diagnosis of angiomyolipoma formed the study group. Patient demographic data was collected, and data from during and after surgery was also reviewed. The median age of the patients was 51 (38-55) years. At presentation, most patients were asymptomatic (6/8, 75%) with the AML presenting as an incidental finding on imaging done for other reasons. There was classical triphasic AML, consisting of elements of adipose tissue, smooth muscle and abnormal blood vessels, in 5/10 tumours (50%). The more aggressive epitheliod variant AML was present in 2/10 (20%). The median follow-up of the patients was 38 (29-64) months. During the follow-up period one (12.5%) patient who had two lesions progressively showed evidence of rising creatinine and decreasing creatinine clearance. AML is a benign renal neoplasm and should be treated initially conservatively. Surgical intervention when required should be nephron sparing so as to reduce the incidence of perioperative complications, loss of renal units, and development of CKD.