Radiofrequency ablation permits an effective treatment for colorectal liver metastasis

Radiofrequency ablation (RFA) has become an important adjunct to modern liver surgery. However, scant knowledge on long-term outcome of RFA for colorectal liver metastasis is available, nowadays.

This is a prospective clinical study of patients with liver metastasis of colorectal cancer who were treated by RFA between April 1, 1998, and November 30, 2004. Forty-seven patients with 147 liver metastases were treated with RFA in a total of 70 interventions. A metastasis resection was not feasible in 80% of the interventions. All the patients were followed up at regular intervals with contrast-enhanced computed tomography (CT) and laboratory tests including carcinoembryonic antigen (CEA).

No RFA-related mortality occurred. The median follow-up time after the diagnosis of liver metastasis was 33 months. The RFA-related morbidity was 7%. After the RFA, the expected median overall survival rate is, to date, 39 months. Overall survival rates at 1, 2 and 3 years were 88%, 80% and 57%, respectively. Local recurrence rates reached 8.8% overall and 1.6% for metastasis smaller than 3cm in diameter. No local recurrence occurred for metastasis smaller than 3cm in diameter if treated with the newest RFA device.

Excellent local tumour control was achieved with radiofrequency ablation of small liver metastasis. The expected overall survival rate of patients with RFA for unresectable or non-resected colorectal liver metastasis improved in comparison with the survival rate reported following the natural course (best supportive care) or chemotherapy. The low local recurrence rate of metastases of less than 3cm challenges the results obtained by the more invasive treatment of conventional liver surgery.