Faculty Bibliography

Purpose: To assess the safety of percutaneous cryoablation for treatment of pulmonary metastases < 3.5 cm. Material and methods: Patients with up to 6 pulmonary metastases were treated in a multicenter, prospective study with CT-guided percutaneous cryoablation. Patient follow-up was performed at 1 week and 3, 6, 12, and 24 months. Complications were assessed using the CTCAE 4.03. Results: Two-hundred nineteen tumors in 126 patients (64 males, 62 females; mean age 64 years) were treated over 163 procedures, constituting the largest prospective multicenter lung cryoablation trial to date. Sixty-two percent (n=78) of the patients had 1 tumor, and 40% had 2 or more. Mean tumor size was 1.2 cm (0.4- 4.5 cm). General anesthesia was employed in 69% (n=113) of procedures, conscious sedation in 29% (n=47), and local anesthesia in 2% (n=3). Treatment time ranged from 30 to 225 min. (mean=72.9 min). Ninety-eight procedure-related events occurred within 30 days of the treatment. Thirty-seven percent were classified CTCAE grade 1 (n=36), 57% grade 2 (n=57), 5% grade 3 (n=5), and 1% grade 4 (n=1). The most frequent event was pneumothorax, of which 8% (n=4) were grade 1, 83% (n=40) grade 2, and 8% (n=4) grade 3. Six percent (n=6) of all events were grade 3 or higher: grade 3 pneumothoraces (n=4), grade 3 pleural hemorrhage (n=1), and grade 4 gas embolism (n=1). All events resolved without further sequelae. Conclusion: Percutaneous CT-guided cryoablation demonstrates an acceptable safety profile for treatment of lung metastases < 3.5 cm