Percutaneous CT-guided thermal ablation as salvage therapy for recurrent non-small cell lung cancer after external beam radiotherapy: A retrospective study

Abstract

Purpose: The aim of this study was to evaluate radiofrequency ablation (RFA) and microwave ablation (MWA) as a viable salvage option for patients with locally recurrent non-small cell lung cancer (NSCLC) after radiotherapy.

Materials and methods: This retrospective study was conducted on patients who had received thermal ablation for recurrent NSCLC post-curative radiotherapy. Medical records and follow-up imaging with computed tomography (CT) and PET-CT were analysed to determine time to local progression (TTLP) and overall survival (OS). TTLP was determined according to the modified RECIST criteria.

Results: Twelve patients, mean age 71 ± 7 years, received 17 thermal ablation sessions, with RFA performed for four lesions and MWA for 13. Nine tumours were squamous cell cancers (SCC) and eight were adenocarcinomas. Eleven tumours had recurred post-external beam radiation and one post-stereotactic body radiation therapy. Mean tumour size was 34.2 ± 12.8 mm, tumour stages prior to radiotherapy were Ia (2), Ib (3), IIa (4), IIb (1) and III (2). Follow-up period was 19 ± 11 months. Overall median TTLP was 14 months (95% CI: 8, 19), and median OS was 35 months (95% CI: 12, 58). Mean TTLP for tumours <30 mm was 23 months and for tumours >30 mm 14 months (p = 0.20). Recurrence rates reduced from 50% after initial ablation to 20% with a second ablation. Complication rate for pneumothorax requiring intervention was 17%.

Conclusion: Both RFA and MWA ablation prolonged local tumour control with minimal morbidity in this study group of recurrent NSCLC after radiotherapy.

Keywords: Microwave ablation; non-small cell lung cancer; radiotherapy; recurrence; salvage.