Percutaneous thoracic cryoablation of primary lung and pleural tumors: Analysis of long-term experience of feasibility, safety, and recurrence parameters

Objectives: The objectives of the study were to report long-term experience with percutaneous thoracic cryoablation, including both malignant pleural and primary pulmonary tumors, assessing factors affecting complications and local recurrence rates. Material and Methods: After Institutional Review Board approval and Health Insurance Accountability Act compliance, a retrospective review of 50 patients who underwent 85 CT fluoroscopic-guided percutaneous cryoablation procedures for 116 masses, consisting of non-small cell lung cancer (n = 61), small cell lung cancer (n = 1), mesothelioma (n = 16) and malignant profile fibrous tumors (n = 38) was performed. Tumor size and location (central vs. peripheral) were noted in relation to major vasculature. Hydrodissection and/or esophageal warming balloons were utilized for the protection of crucial structures. Complications were graded according to standardized Common Terminology Criteria for Adverse Events criteria. Patients were followed by CT and/or MRI at 1, 3, 6, 12, 18, and 24 months and yearly, thereafter. Results: Mean tumor diameter was 3.3 cm and 3.0 cm for primary lung tumors (PLTs) and malignant pleural tumors (MPTs), respectively. The mean number of cryoprobes utilized was 3.7 per tumor, which produced ablation zones with CT visible ice mean diameters of 5.3 cm. Hydrodissection and/or warming balloon protections were used in 15.3% (n = 13/85). Grade ≥3 complications were limited to tumors >3 cm (8.2% = 7/85; P = 0.0042), but did not appear significant for central location. At a mean follow-up of 17.0 months, overall local tumor recurrence was 6.9% (n = 8/116). Pleural tumors had lower recurrence rates than PLTs (1.8% [n = 1/54] vs. 11.3% [n = 7/62], respectively; P 3 cm or central location had statistically significant higher recurrence rates, (P = 0.021) and (P = 0.039), respectively. Central recurrences occurred predominantly in tumors >3 cm (20%, n = 5/25). Conclusion: With appropriate pre-treatment, evaluation, and procedural criteria, percutaneous cryoablation of both primary lung and pleural tumors is safe and produces very low local recurrence rates, especially for tumors ≤3 cm.