Microwave Ablation of Refractory Oligometastatic Non-Small Cell Lung Cancer in the Liver.

PURPOSE

To evaluate safety and effectiveness of microwave ablation (MWA) in the treatment of liver metastases (LMs) secondary to non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

This retrospective study included patients with NSCLC who underwent MWA of LM from March 2015 to July 2022. Local tumor progression-free survival (LTPFS) and overall survival (OS) were estimated using competing risk analysis and the Kaplan-Meier method. Postprocedural adverse events were recorded according to the Common Terminology Criteria for Adverse Events (CTCAE) v5.0.

RESULTS

Twenty-three patients with 32 LMs were treated in 27 MWA sessions. The mean dimension of the largest index tumor was 1.96 cm (SD ± 0.75). Technical success was 100%. Technical effectiveness was achieved in 26 (81.3%) of 32 tumors. The median length of follow-up was 37.7 months (interquartile range, 20.5-54.5 months). The median LTPFS was 16.3 months (95% confidence interval [CI], 7.87-44.10 months). The median OS was 31.7 months (95% CI, 11.1-65.8 months). Ablation margin was a significant factor for LTPFS, with tumors ablated without a measurable margin being more likely to progress than those with measurable margins (subdistribution hazard ratios [HRs], 0.008-0.024; P < .001). Older age (HR, 1.18; 95% CI, 1.09-1.28; P < .001) and presence of synchronous lung metastases (HR, 14.73; 95% CI, 1.86-116.95; P = .011) were significant predictors of OS. Serious adverse events (CTCAE Grade ≥3) within 30 days occurred in 2 (7.4%) of 27 sessions, including pulmonary embolus and severe abdominal pain.

CONCLUSIONS

Percutaneous MWA was a safe treatment for NSCLC LM, with longer survival noted in younger patients and those without synchronous lung tumors.