Percutaneous Microwave Lung Tumor Ablation: A Single Center Mid-Term Experience
To evaluate overall survival, disease free progression, and tumor control following percutaneous microwave ablation of primary and metastatic lung tumors performed at a single institution.
•Under IRB exemption, our institution’s MW ablation database was retrospectively reviewed for all percutaneous microwave lung ablations performed between August 2011 and August 2016.
•All ablations performed using a high-powered gas-cooled microwave system (Neuwave Medical, Madison WI).
•Patients divided into two study groups for further analysis: a) primary lung tumors and b) lung metastases.
•Tumor and ablation parameters were recorded and follow-up imaging was reviewed for local and distant tumor progression.
•Complications were recorded and categorized according to the SIR classification system.
•Overall (OS) and progression-free survival (PFS) were calculated via a Kaplan-Meyer analysis.
•Median number of ablation probes used: 1
•Mean treatment power: 63 W
•Mean ablation time: 7 minutes
•Technical success rate: 100%
•The most commonly encountered complication was pneumothorax, occurring in 76% (29/38) of sessions. Of that group, chest tubes were only required in 17% (5/29) of cases, for an overall rate of 13% (5/38) in all patients undergoing lung MW. All chest tubes removed within 2 days.
•There were only two major complications: a single case of recurrent pleural effusion requiring serial thoracenteses, and a single case of aspergilloma development within an ablation cavity requiring oral antifungal therapy in a radiation failure patient.
•No broncho-pleural fistulas in this study.
•Median imaging follow-up:
23 months in metastatic group
17 months in primary lung group
•Local tumor progression:
19.1% in lung primary group (4/21)*
19.2% in metastases group (5/26)
•Distant tumor progression:
21.4% in both groups*
*Note that a large number of primary lung malignancy patients had previously undergone surgical/SBRT or other treatment (9/21) and were not treated with MW de novo
•Overall survival and progression-free survival are shown in Figures 1 and 2, respectively.
•Our institutional results demonstrate that high-powered microwave can be safely utilized in the lung, with a favorable complication profile favorable
•Our study is limited by a large number of primary lung tumor ablations performed as salvage therapy. Despite this limitation, MW ablation remains an effective modality for treatment of primary and metastatic pulmonary malignancy