Percutaneous radiofrequency ablation improves the outcomes of patients with colorectal cancer liver metastases

This study investigated the effectiveness and safety of percutaneous radiofrequency ablation (PRA) in the treatment of colorectal cancer (CRC) liver metastases (LM). Researchers suggested that PRA is a good and safe method for the treatment of these patients. 

CRC is a common cancer worldwide, affecting 4.3% of men and 4% of women. Around 25% of patients present with liver metastases (cancer spread to the liver) at diagnosis. Less than 20% of these patients are eligible for surgery to remove the metastases.

PRA involves inserting a needle in the tumor and a generator delivers energy to destroy the tumor. Prior studies showed that PRA is safe and improves local control of the disease and survival. 

However, PRA has only limited effectiveness against subcapsular tumors. These tumors are located under a thin layer that covers the organ surface (capsule). One prior study reported a 1.9 times higher risk of local tumor progression in patients treated with PRA. However, other studies have conflicting results reporting no significant difference in cancer outcomes after treatment with PRA. The effectiveness of PRA to treat subcapsular liver metastases in patients with CRC is still not clear.

This study included 199 patients with CRC and liver metastases. All patients underwent PRA. Patients with subcapsular tumors were assigned to group 1, and the remaining patients to group 2. The main outcomes measured were effectiveness, complications, tumor progression, and overall survival (OS; time from treatment to death by any cause).

Effectiveness of PRA was achieved in 93.5% of the liver metastases. 5.5% of patients had complications. The minimal ablative margin (tissue around the tumor that is also removed during surgery) in group 1 was smaller when compared to group 2. 

With an average follow-up time of 23 months, tumor progression was seen in 37.1% of all patients. 96.1% of patients were alive after 1 year. At 3 years this rate was 66%, and at 5 years it was 44.2%. No significant difference was seen between both groups for effectiveness, complications, progression-free survival, and OS. 

Factors that predicted the progression of disease were smaller ablative margins and tumors larger than 2 cm.

This study concluded that PRA is a good and safe method of treatment for subcapsular colorectal cancer liver metastases. 

This study was based on medical records from a single medical center. Patients data might be missing which affects study results. Further studies are necessary.