Radiofrequency ablation versus microwave ablation for lung cancer/lung metastases: a meta-analysis

Background: Both radiofrequency ablation (RFA) and microwave ablation (MWA) are commonly used non-surgical treatment methods for lung cancer/lung metastases (LC/LM). However, there is still debate over which one is superior. The meta-analysis was conducted to evaluate the effectiveness and safety between the two groups.

Methods: Seven databases were systematically searched for relevant literature comparing RFA versus MWA in the treatment of LC/LM. The primary outcome assessed was survival, while secondary outcomes included ablation efficacy rate, recurrence, and complications.

Results: Ten studies were included, comprising 433 patients in the RFA group and 526 in the MWA group. The RFA group exhibited longer overall survival (OS) time (mean difference [MD]: 1.95 [0.43, 3.48] months) and progression-free survival (PFS) time (MD: 3.00 [2.31, 3.69] months) compared to the MWA group. Progression-free survival rates (PFSR) at 1 and 2 years were superior in the RFA group, with the advantage of PFSR increasing with prolonged survival time. However, the ablation duration (MD: 5.78 [3.54, 8.01] min) was longer in the RFA group. Both groups showed similar rates of recurrence, complete ablation (initial and subsequent sessions), total complications, as well as grade 1-2 and grade 3-4 complications. The top 5 complications in the total population were pneumothorax (26.63%), pleural effusion (17.22%), subcutaneous emphysema (14.31%), intra-alveolar haemorrhage (9.72%), and post-ablation syndrome (8.88%).

Conclusions: RFA appears to be more effective than MWA in the treatment of LC/LM, showing improved survival (OS and PFS) and comparable safety.