Microwave ablation of malignant lung lesions;safety and efficacy – the King’s experience

Introduction: Microwave ablation (MWA) is a treatment option for primary lung cancer and pulmonary metastasis aiming to destroy tumor cells and create localised areas of tissue necrosis with minimal damage to surrounding normal tissues. Objectives: To audit the MWA service in patients with primary lung cancer/pulmonary metastases treated at King’s College hospital from 09/2014 to 09/2016. Materials and Methods: Retrospective case review of all patients who underwent MWA between 09/2014 and 09/2016. All patients were highly selected and offered MWA after due consideration of the alternatives by the lung cancer MDT. Percutaneous MWA was performed under general anaesthesia. Lesions were targeted using image guidance and tumours ablated by delivering high-frequency microwave energy (140 W) with mean ablation time 2-3 minutes. Results: 15 patients are reported (8 females, mean age 60 years). 4 patients (27%) had primary lung cancer and 11 patients (73%) pulmonary metastases (mainly from colorectal primary). Four patients had MWA to two lesions. There was a complete response in 5 patients (33%), partial response in 2 patients (13%) and stable disease in 2 patients (13%), progressive disease in 4 patients (26%). The most common complication was pneumothorax (7 patients, 47%) - 2 patients requiring tube drainage/admission (duration 14,21 days). One patient sustained chest wall soft tissue damage.14/15 patients are alive after a mean follow-up period of 7 months (range 1 day to 19 months). Conclusion: MWA has a role in the management of primary lung cancer and pulmonary metastases. The most common complication in our series was pneumothorax.