FDG-PET and colon cancer

Imaging colorectal cancer has become a major indication for positron emission tomography using fluorodeoxyglucose (FDG-PET). In primary diagnosis and staging, the role for this technique is limited but FDG-PET has proved highly accurate in the detection of recurrent tumour. The three main indications are (i) characterisation of a residual structural lesion after definitive therapy, (ii) pre-operative staging prior to resection of apparently isolated metastasis, and (iii) investigation of rising carcinoembryonic antigen (CEA) in a patient with normal structural imaging. The diagnostic accuracy of FDG-PET translates to changes in management in a large number of patients, resulting in improved cost-effectiveness. FDG-PET is fast becoming the standard of clinical care for patients with recurrent colorectal cancer.