Local control, safety, and survival following image-guided percutaneous microwave thermal ablation in primary lung malignancy

To determine local control, safety, and survival following percutaneous computed tomography (CT)-guided high-power microwave ablation (MWA) in the treatment of primary lung malignancy at a single institution. From July 2010 to June 2016, 52 patients (mean age 76.3 years, range 55–91 years) with 61 unresectable primary lung cancers of mean diameter 23.8 mm (range 26–55 mm) underwent MWA in 55 ablation sessions. Tumours were diagnosed at biopsy, or positron-emission tomography (PET) avidity (mean SUV max = 10.51) and interval growth. Statistical analysis was performed by Kaplan–Meier modelling and Cox and logistic regression. Local tumour progression (LTP) was diagnosed in six lesions (10%). Median time to local recurrence was 3 months (range 2–14 months). There was a near 12-fold increased odds of local recurrence if the lesion size was >3 cm (95% confidence interval [CI]: 1.84–75.14; p=0.009). The median inpatient stay was 1 day, with no intra-procedural deaths and a 0% 30-day post-ablation mortality rate. Pneumothorax requiring drain was the most serious complication, occurring in 22% (n=12) of patients. Presence of severe emphysema and predicted forced expiratory volume in 1 second (FEV1) of 3 cm had a hazard ratio of 4.37 compared with tumour size ≤3 cm (95% CI: 1.45–13.17, p=0.009) of risk of cancer death at any time, by Cox regression. MWA for primary lung malignancy is a safe and effective treatment for primary lung tumours with outcomes that may be comparable to stereotactic body radiation therapy. •MWA for primary lung malignancy is a safe and effective treatment for early-stage non-small cell lung cancer.•At minimum follow up of 12 months rates of local tumour progression and survival are comparable to stereotactic body radiotherapy (SBRT).•Percentage-predicted FEV1 and presence of severe emphysema were risk factors for the occurrence of a pneumothorax requiring a drain.•Maximal tumour diameter was associated with cancer-specific mortality.