Introduction: To assess the feasibility, safety and local tumor control of cryoablation for treatment of pulmonary metastases.
Materials and methods: This Health Insurance Portability and Accountability Act (HIPAA) compliant, IRB-approved, multicenter, prospective, single arm study included 40 patients with 60 lung metastases treated during 48 cryoablation sessions, with currently a minimum of 12 months of follow-up. Patients were enrolled according to the following key inclusion criteria: 1 to 5 metastases from extrapulmonary cancers, with a maximal diameter of 3.5 cm. Local tumor control, disease-specific and overall survival rates were estimated using the Kaplan-Meier method. Complications and changes in physical function and quality of life were also evaluated using Karnofsky performance scale, Eastern Cooperative Oncology Group performance status classification, and Short Form-12 health survey.
Results: Patients were 62.6 ± 13.3 years old (26-83). The most common primary cancers were colon (40%), kidney (23%), and sarcomas (8%). Mean size of metastases was 1.4 ± 0.7 cm (0.3-3.4), and metastases were bilateral in 20% of patients. Cryoablation was performed under general anesthesia (67%) or conscious sedation (33%). Local tumor control rates were 56 of 58 (96.6%) and 49 of 52 (94.2%) at 6 and 12 months, respectively. Patient's quality of life was unchanged over the follow-up period. One-year overall survival rate was 97.5%. The rate of pneumothorax requiring chest tube insertion was 18.8%. There were three Common Terminology Criteria for Adverse Events grade 3 procedural complications during the immediate follow-up period (pneumothorax requiring pleurodesis, noncardiac chest pain, and thrombosis of an arteriovenous fistula), with no grade 4 or 5 complications.
Conclusion: Cryoablation is a safe and effective treatment for pulmonary metastases with preserved quality of life following intervention.