33 - Impact of Multiple Ablations vs. Single Ablation Procedures for Treatment T1a Renal Cell Carcinoma (RCC): Evaluation of Adverse Event Rates and Long-Term Oncologic Outcomes

Sunday, April 12, 2026

3:18 PM - 3:27 PM ET

Presenting Author(s)

DC

Derek W. Cool, MD, PhD

Radiologist - Assistant Professor
Department of Medical Imaging, Western University, London ON, Canada, Canada

Author/Co-author(s)

SA

Shaima Albuqasim, MD

Interventional Radiologist
Riad, Saudi Arabia
RL

Rahman Ladak, BS

Medical Student
Schulich School of Medicine & Dentistry, Western University, Canada
Fu (Jorden) Lo, MD, BSc

PGY2 in Diagnostic Radiology
London Health Sciences Centre, Canada
GW

Ginger Watts, MD

Assistant Professor
Dept of Medical Imaging, Western University, London, ON, Canada, Canada
LC

Leandro Cardarelli Leite, MD

Interventional Radiologist
University of Western Ontario, Canada
SP

Stephen Pautler, MD

Professor
Division of Urology, Dept of Surgery, Western University, London, Ontario, Canada, Canada
JI

Jonathan Izawa, MD

Professor
Division of Urology, Dept of Surgery, Western University, London, Ontario, Canada, Canada
JC

Jospeh Chin, MD, FRSC

Professor of Surgery
London Health Sciences Centre, Canada
AM

Amol Mujoomdar, MD FSIR

Professor of Interventional Radiology, Oncology and Medical Biophysics
Western University, Canada

Purpose: To determine whether successful RCC ablation in a single procedure (primary technical success) or multiple procedures (secondary technical success) impacts adverse event rates or oncologic outcomes.

Materials and Methods: A retrospective study of all percutaneous ablation procedures from January 1, 2004-July 31, 2022 was performed identifying patients with solitary, de novo biopsy-confirmed T1a (≤4.0cm) RCC treated with percutaneous ablation at a single institution. Exclusion criteria included: presence of metastatic disease at time of ablation, multiple synchronous RCC tumors, prior RCC therapy, or failure to achieve successful ablation. Successful ablation was defined as no viable tumor on follow-up cross-sectional imaging after a single (primary technical success) or multiple ablation procedures (secondary technical success). Total of 269 patients with solitary biopsy-confirmed RCC (clear cell-65%, papillary-22%, chromophobe-6%, other-7%) met inclusion criteria. Ablations were performed by 9 interventional radiologists with a median follow-up of 5.1 years (IQR 3.8-7.9). Adverse events were tabulated as per 2023 SIR classification {1} and evaluated oncologic outcomes included disease recurrence, local tumor progression (LTP), and metastatic disease/new RCC lesions (Mets).

Results: 247 patients (92%) were treated with single ablation (median age–67 years, M:F 172:75, tumor size – 2.7 cm; RENAL-6; Charlson Comorbidity Index-5; RFA/MWA:Cryoablation-190:57) and 22 (8%) had multiple ablation procedures (age-73 years, M:F 15:7; tumor size-2.8 cm; RENAL-6; CCI-6; RFA/MWA:Cryoablation-12:10; 2 ablations=20, 4 ablations=2). Per patient moderate or higher adverse events were not significantly different (p=0.71) between patients with a single ablation procedure (6.5%,16/247 patients) vs. multiple ablation procedures (4.5%, 1/22 patients). Rates of RCC disease recurrence, LTP and Mets were similar between the two groups with 12% (29/247), 9% (21/247), & 4% (12/247), respectively, in the single ablation cohort and 18% (4/22), 14% (3/22), & 4% (1/22) in the multiple ablation group. Kaplan-Meier estimation of 5-year survival showed no significant difference between single ablation and multiple ablations for disease-free survival (87.9% vs. 89.7%, p=0.55), metastasis-free survival (95.1% vs. 95%, p=0.9), and overall survival (88.2% vs. 79.4%, p=0.79), respectively.

Conclusion: Successful RCC ablation in a single procedure or over multiple procedures does not appear to have a detrimental impact on long-term oncologic outcomes or adverse event rates.