Percutaneous Microwave Ablation of Renal Angiomyolipomas

Cardiovasc Intervent Radiol. 2016 Mar;39(3):433-40. doi: 10.1007/s00270-015-1201-5. Epub 2015 Sep 21.

Abstract

Purpose: To evaluate the safety and efficacy of US-guided percutaneous microwave (MW) ablation in the treatment of renal angiomyolipoma (AML).

Materials and methods: From January 2011 to April 2014, seven patients (5 females and 2 males; mean age 51.4) with 11 renal AMLs (9 sporadic type and 2 tuberous sclerosis associated) with a mean size of 3.4 ± 0.7 cm (range 2.4-4.9 cm) were treated with high-powered, gas-cooled percutaneous MW ablation under US guidance. Tumoral diameter, volume, and CT/MR enhancement were measured on pre-treatment, immediate post-ablation, and delayed post-ablation imaging. Clinical symptoms and creatinine were assessed on follow-up visits.

Results: All ablations were technically successful and no major complications were encountered. Mean ablation parameters were ablation power of 65 W (range 60-70 W), using 456 mL of hydrodissection fluid per patient, over 4.7 min (range 3-8 min). Immediate post-ablation imaging demonstrated mean tumor diameter and volume decreases of 1.8% (3.4-3.3 cm) and 1.7% (27.5-26.3 cm(3)), respectively. Delayed imaging follow-up obtained at a mean interval of 23.1 months (median 17.6; range 9-47) demonstrated mean tumor diameter and volume decreases of 29% (3.4-2.4 cm) and 47% (27.5-12.1 cm(3)), respectively. Tumoral enhancement decreased on immediate post-procedure and delayed imaging by CT/MR parameters, indicating decreased tumor vascularity. No patients required additional intervention and no patients experienced spontaneous bleeding post-ablation.

Conclusion: Our early experience with high-powered, gas-cooled percutaneous MW ablation demonstrates it to be a safe and effective modality to devascularize and decrease the size of renal AMLs.

Keywords: AML; Percutaneous microwave ablation; Renal angiomyolipoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Angiomyolipoma / therapy*
  • Catheter Ablation / methods*
  • Female
  • Humans
  • Kidney Neoplasms / therapy*
  • Male
  • Microwaves / therapeutic use*
  • Middle Aged
  • Retrospective Studies
  • Tuberous Sclerosis / therapy
  • Ultrasonography, Interventional
  • Young Adult

Supplementary concepts

  • Tuberous Sclerosis 2