Login to Access Video or Poster Abstract: MP18-14
Sources of Funding: This research was made possible through the National Institutes of Health (NIH) Medical Research Scholars Program, a public-private partnership supported jointly by the NIH and generous contributions to the Foundation for the NIH from the Doris Duke Charitable Foundation, The American Association for Dental Research, the Colgate-Palmolive Company, Genentech and alumni of student research programs and other individual supporters via contributions to the Foundation for the National Institutes of Health.

Introduction

Radiofrequency ablation (RFA) has become an acceptable nephron-sparing treatment for small renal masses. It is sometimes considered for patients with high likelihood of repeat interventions, such as those with multifocal lesions from hereditary syndromes. Available long-term renal functional outcomes for patients with multiple lesions are limited predominantly to the surgical approach, and little is known about the effect of multiple tumor ablations in single procedure. Our aim is to compare the long–term renal functional changes for patients who had a single lesion vs. of multiple lesions treated with RFA.

Methods

Our institution review board approved study registry was queried for patients treated using RFA with single or multiple ablation zones. This series was limited to first ablative procedures, and follow-up was censored to time of next surgical or interventional procedures. Clinical features and renal functional outcomes as measured by change in eGFR and rate of eGFR<45 were compared between groups._x000D_

Results

Overall, 63 patients met inclusion criteria and had 89.7 median months of follow-up. Of these 46 (73.0%) underwent single vs 17 (27.0%) underwent multiple tumor ablation during a single procedure. Patients who had multiple tumors ablated were had greater total tumor volume (median volume 14.5cm3 vs 9.2cm3, p < 0.001), were more likely to have been treated laparoscopically (47.1% vs 13.0%), but had similar age, gender distribution, BMI, baseline eGFR, overall survival, and length of follow-up. The rate of hereditary syndrome diagnosis between the multiple vs single ablation groups were significantly different (p<0.001): Von Hippel-Lindau (76.4% vs 84.7%), familial oncocytoma (5.9% vs 2.2%), hereditary papillary renal cancer (11.8% vs 2.2%), Birt-Hogg-Dube (11.8% vs 2.2). Multiple and single tumor ablations were associated with a similar median change in eGFR (mL/min/1.73 m2 ) at 1 year (-6.60 vs. -1.65, p=0.306), and at last follow-up (-22.0 vs. 18.9 p=0.676), as well as freedom from GFR<45 at last follow-up (5.9% vs. 4.3%, p=0.618).

Conclusions

In this series, multiple and single tumor ablations were associated with similar renal functional outcomes. These data suggest that multiple tumors can be safely ablated in patients with multifocal disease.

Funding

This research was made possible through the National Institutes of Health (NIH) Medical Research Scholars Program, a public-private partnership supported jointly by the NIH and generous contributions to the Foundation for the NIH from the Doris Duke Charitable Foundation, The American Association for Dental Research, the Colgate-Palmolive Company, Genentech and alumni of student research programs and other individual supporters via contributions to the Foundation for the National Institutes of Health.