Because accurate electrode placement is pivotal in achieving adequate tumor necrosis, RFA should not be performed percutaneously when electrode placement is impaired. We suggest that lesions >5 cm and lesions located near great vessels or adjacent organs should be treated with open RFA, thus allowing vascular inflow occlusion and complete mobilization of the liver. Lesions that are difficult to reach by electrodes should be approached by an open procedure.

The procedure-specific complication rate was almost 10 per cent and it is recommended that RFA should be performed only by an experienced team comprising a hepatobiliary surgeon, gastroenterologist, hepatologist and interventional radiologist. Biliary stricture, hepatic vascular damage and hepatic abscesses were the most common major complications.

These results show that following PDT, RFA and HAI resistance to local and possibly systemic tumour rechallenge is increased. This may be partly due to the induction or enhancement of a cellular immune response.