Safety and Effectiveness of Non-Small Cell Lung Cancer Cryoablation and Microwave Ablation Involving Previously Irradiated Lung.

[PURPOSE] To report outcomes of cryoablation and microwave ablation (MWA) of non-small cell lung cancer (NSCLC) in and adjacent to previously radiated lung.

[MATERIALS AND METHODS] This retrospective cohort study included consecutive patients who underwent percutaneous cryoablation or MWA of NSCLC located in or adjacent to lung radiation fibrosis from April 2015 to October 2024. Adverse events (graded according to the Society of Interventional Radiology [SIR] classification system) within 30 days after ablation and hospital length of stay (HLOS) were compared between modalities using logistic regression. Local tumor progression-free survival (LTPFS) and overall survival (OS) were compared between modalities using log-rank testing. Twenty-three patients (14 women; median age, 76 years) underwent 24 ablations (18 cryoablations and 6 MWAs) of 23 NSCLCs (median diameter, 21 mm; 1 tumor per patient).

[RESULTS] Grade ≥3 adverse events occurred following 2 cryoablations (11%), including hemothorax and intercostal neuralgia, and 2 MWA sessions (33%), including pain and fatigue (P = .238). Two pneumothoraces requiring drainage (SIR Grade 2) occurred following cryoablations (11%). Median HLOS was 1 day for both groups (P = .730). LTPFS rates were 80% at 12 months and 66% at 24 months and higher for cryoablation (P = .022). After a median imaging follow-up of 12 months (interquartile range, 10-23 months), 11 patients died. OS rates were 80% at 12 months and 57% at 24 months with no significant difference observed between ablation modalities (P = .527).

[CONCLUSIONS] Differences in safety and effectiveness were observed following percutaneous cryoablation and MWA of NSCLC located in or adjacent to previously radiated lung, although statistical certainty is limited by sample size.