Renal Functional Outcomes in Patients With Angiomyolipomas: Surveillance vs Embolization vs Nephrectomy

To investigate renal functional outcomes of surveillance, embolization, and surgery for angiomyolipomas (AML).

Longitudinal data regarding patients with AML were analyzed retrospectively in this 2-center study. Demographic, radiographic, and functional data were tabulated according to treatment type. Primary outcome was change in renal function from diagnosis to within 6 months postdiagnosis (interim) and to latest glomerular filtration rate (GFR) assessment.

318 patients were diagnosed with AMLs; mean follow-up was 6.2 years. 184 patients (57.9%) were managed with surveillance, 30 (9.4%) underwent embolization, and 103 (32.4%) underwent surgery (91 partial nephrectomy; 12 radical nephrectomy). Baseline characteristics, including tumor size, age, and race differed between the 3 groups (P<.05). Surveilled AMLs were smaller (P<.001) than the intervention groups: 1.9 cm vs 5.4 cm (embolization) and 4.9 cm (surgery). Greater interim decreases in GFR were observed following intervention with embolization (-14.0%) or surgery (-11.8%), when compared with surveillance (-4.1%); however, this was not statistically significant (P=.19). Latest GFR was also reduced more (P=.02) with embolization (-14.1%) and surgery (-14.7%) when compared to surveillance (-6.0%). At latest determination, chronic kidney disease progression by at least one stage occurred in 37.8% overall, including 33.7% of surveilled patients, and was not statistically different across the three cohorts (P=.074).

Within the study limitations, surveillance appears to be appropriate for most AML patients; embolization and surgical intervention should be reserved for selected patients with large and/or symptomatic AML. Renal functional deterioration is common in patients with AML, whether managed with surveillance, embolization, or surgery. Long-term monitoring of renal function should be obligatory for all AML patients.