Treatment for lung metastases: how good is radiofrequency ablation for colorectal cancer patients?

This study investigated the effectiveness of radiofrequency ablation (RFA) for patients with colorectal lung metastases (cancer that has spread from the colon or rectum to the lung).

Colorectal cancer is one of the most common cancers worldwide. For up to 25% of patients the colon or rectal cancer will have spread to a distant organ by the time they are diagnosed. One of the most common sites for the cancer to spread is the lung. As a result, it is important to improve treatments for destroying cancer cells in patients’ lungs.

A minimally invasive treatment called RFA is an alternative treatment to lung surgery. RFA uses electrical energy to heat and destroy cancer cells. Previous studies have reported complete destruction of lung cancer cells using RFA.  

This study examined the effectiveness of RFA in 566 patients with small lung metastases (below 2 and 3 cm). 34% of patients had colon cancer, 18% had rectal cancer, and 48% of patients had cancer in other organs. All patients underwent general anesthesia or received sedation before undergoing RFA. Patients were followed-up for an average of 35.5 months after RFA. Patient survival and time until cancer progression (increased growth of the cancer) were assessed during the follow-up.

75% of patients spent less than 4 days in hospital after undergoing RFA and 1.7% spent more than 9 days in hospital. 24% of patients needed more than one session of RFA due to the first session failing.

1 year after RFA 92.9% of colon cancer patients were still alive and after 5 years 56% were still alive. After 1 year the cancer had progressed for 62.4% of colon cancer patients and for 85.2% after 5 years.

1 year after RFA 93.6% of rectal cancer patients were still alive and after 5 years 49.6% were still alive. After 1 year the cancer had progressed for 69.6% of colon cancer patients and for 93.6% after 5 years.

The most common adverse event was pneumothoraces (collapsed lung; a build-up of gas and air in the membrane surrounding the lung). This build–up of air and gas occurred in 67% of patients during the RFA procedure. Patients required no additional treatment (28%), had the air or gas sucked out during RFA (14%), or had a chest tube inserted to drain the air out of the lining of the lungs (58%).

The authors concluded that RFA is an option for the treatment of small size lung metastases. They also highlighted that rates of survival after RFA are similar to those reported after lung surgery.