The RAPTURE study, led by Riccardo Lencioni of Cisanello University Hospital in Italy, examined 106 patients with 183 malignant lung tumours (of 3.5 cm or less in diameter). Non small-cell lung cancer (NSCLC) was diagnosed in 33 patients, metastasis from colorectal carcinoma in 53 and metastasis from other primary malignancies in 20. All patients were rejected for surgery and considered unfit for radiotherapy or chemotherapy.
The study participants underwent RF ablation and were then followed for up to two years. A confirmed complete tumour response that lasted for at least one year after treatment was seen in 75 out of 85 assessable patients.
The cancer-specific survival rates at one and two years were 92% and 73%, respectively, in patients with NSCLC; 91% and 68% in patients with colorectal metastases; and 93% and 67% in patients with other metastases. The 13 patients with stage I NSCLC had a two-year overall survival of 75% and a two-year cancer-specific survival of 92%.
The researchers note that the ablation device was correctly placed in 99% of the patients, and that no procedure-related deaths occurred in any of the 137 ablation sessions. Major complications included pneumothorax in 27 procedures and pleural effusion in four, but no significant decline in lung function was seen.
The authors of the Lancet Oncology paper concluded: "Our study shows that radiofrequency ablation can be completed successfully in high percentage of patients with small lung tumours. The safety profile of the procedure was also acceptable, with no mortality or life-threatening complications associated with it. A randomised controlled trial comparing RF ablation versus standard treatment options is now warranted to prove the clinical benefit of this approach."