Comparison of Microwave and Radiofrequency Ablation in the Treatment of Pulmonary Metastasis of Colorectal Cancer.

Abstract

Radiofrequency ablation (RFA) for colorectal cancer pulmonary metastases (CRCPulM) has been shown to be safe. Microwave ablation (MWA) has emerged in the treatment for CRCPulM. However, short to long-term efficacy of both modalities have yet to be understood. This is a retrospective study of 203 patients who received RFA and MWA from 2000-2018 at a major tertiary hospital in Australia. A total of 161 patients underwent RFA and 42 MWA. Median ablation size and time was 4 (range=3-5 cm) vs. 3.5 cm (range=3-4 cm; p=0.0395) and 49 (range=26-65 min) vs. 8 min (5-13 min) in the RFA and MWA groups, respectively (p<0.001). The complication rate was 112 (55%) and 40 (74%) in the RFA and MWA group, respectively (p=0.011). Life-threatening pulmonary haemorrhage occurred in 1 (0.5%) and 4 (7.4%) patients in the RFA and MWA group, respectively (p=0.007). Local recurrences detected after discharge were similar in both groups [28% (p<0.001)]. However, the MWA group demonstrated higher survival rate and less recurrence rate than RFA in the first 24 months of follow up. RFA and MWA are competitive treatment methods for CRCPulM. Although MWA has significantly higher complication rate than RFA, it can be performed in a much shorter time and lead to a shorter length of hospital stay.