Monitoring the success of radio-frequency ablation of liver metastases using 18F-FDG PET imaging

Full text: A 60-year-old man was diagnosed with Duke's B Cell carcinoma of the large bowel in 1996. Following resection of the tumour and chemotherapy, he remained asymptomatic until 1999 when increases in CEA indicated a possible recurrence of disease and metastases were found in the liver. He underwent embolisation of the liver and chemotherapy through an hepatic infusaport in 1999. The liver metastases were treated by radiofrequency ablation (RFA) in 2000 Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) scans showed that the lesions had decreased in size, however, a whole body 2-[18F]Fluoro 2 Deoxy-D-Glucose. (18F-FDG) Positron Emission Tomography (PET) scan was also performed. This scan showed foci of activity at the sites of the residual disease, indicating that this patient was not in remission as thought after CT and MRI scans. After a second RFA treatment in February 2001, a repeat PET scan demonstrated continuing tumour uptake at both sites. A third PET scan three months later showed multiple foci in the liver. These lesions were then seen on CT and MRI scans. Subsequently, 70% of his liver was surgically removed and he received further chemotherapy. PET scans were used to monitor the tumour response to further treatment and proved to be a more sensitive test for disease than CT or MRI. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc