Abstract No. 542 Microwave Ablation versus Cryoablation for T1a Renal Cell Carcinoma: A Systematic Literature Review and Meta-Analysis

Abstract

To conduct a systematic literature review and meta-analysis on microwave ablation (MWA) and cryoablation (CA) for T1a renal cell carcinoma (RCC). A systematic search was performed in MEDLINE, Embase, and Cochrane databases. RCTs and observational studies published in English from January 2006-February 2022 that treated adults with T1a RCC using MWA or CA were included. Overall, 22 MWA and 13 CA arms were included. Outcomes studied were procedure/ablation time, overall/major complications, technical success, and primary technique efficacy (PTE, 1-3 months post ablation), local tumor recurrence (LTR), disease-free survival (DFS), and overall survival (OS). Single-arm meta-analyses were performed using random effects model for outcomes for which at least 2 studies were available for both MWA and CA. Estimates based on single-arm pooling of results showed similar results with MWA and CA for all outcomes except lower ablation times for MWA (Table). MWA procedure and ablation times were 72.75 and 7.63 mins and 126.30 and 30.00 mins with CA, respectively. Overall and major complications were 5% and 3% with MWA, and 9% and 4% with CA, respectively. Technical success was 97% with MWA and 96% with CA. PTE was 94% with MWA and 91% with CA. LTR at 1 and 2-year were both 2% for MWA and 4% and 7% for CA, respectively. DFS was 95% with MWA and 91% with CA at 1 year. OS ranged from 98% at 1-year to 87% at 5-year with MWA, and 96% to 85% for CA, respectively. In T1a RCC patients treated with ablations, MWA shows similar safety and clinical effectiveness compared with CA with lower ablation time.