Long-term Observation of CT-guided Radiofrequency Ablation of Lung Neoplasm in 476 Consecutive Patients by a Thoracic Surgical Service: A Single-institutional Experience

Abstract

The aim of the study was to evaluate the overall survival (OS) rate, progression survival rate, and local control rate over 10 years of medically inoperable patients with lung cancer undergoing computed tomography (CT)-guided radiofrequency ablation (RFA). Between September 2004 to March 2016, 668 neoplasms were treated in 476 medically inoperable patients (294 men, 60 women; median age 74 years; range 29-84) who underwent CT-guided RFA. All patients had clinical or pathologic evidence of the neoplastic lesion: 22.1% patients with primary non-small cell lung cancer (NSCLC), 22.3% patients with recurrent NSCLC, 45.2% with metastases, and 10.3% with small cell lung cancer. The mean size of the lesions was 3.8 cm (range of 1-16 cm). Twenty-one lesions were re-treated from one to as many as four times. The procedure was technically successful in all cases. No procedure-related deaths occurred in the RFA procedures. Major complications consisted in 104 (21.8%) cases of low-grade fever, 46 (9.6%) of the pneumothorax. The mean follow-up was 32 months. The probabilities of 1-, 2-, 3-, 5-, and 10-year OS rate were 98.1%, 86.6%, 68.9% 34.5%, and 9.5% for primary NSCLC; 59.7%, 18.5%, 8%, 3.4%, and 1.5% for metastases; 93.3%, 59.1%, 49.6%, 19.7%, and 0% for recurrence; and 89.4%, 67.5%, 39.1%, 16.5%, and 0% for small cell lung cancer. In primary NSCLC, progression-free survival (PFS) and OS were significantly related to tumor size, but there was no significant difference in recurrent NSCLC, metastasis, and peripheral SCLC. The median OS of metastases of NSCLC was significantly related to nodal or distant metastases. The most common pattern of recurrence was local; any type of recurrence at 1-year follow-up imaging was seen in 7.1% of primary NSCLC diameter less than 3 cm. Our experience indicates that CT-guided RFA done by the thoracic surgeons is feasible and safe in high-risk patients. Maximum tumor diameter less than 3 cm and lack of extrapulmonary metastasis are all positive prognostic factors of survival after RFA. RFA offers good local control of recurrent NSCLC, lung metastases, and SCLC, also in the long-term period. RFA should continue to offer an alternative option in medically inoperable patients.