Role of FDG-PET/CT in detection of recurrent disease in colorectal cancer

Background One-third of patients with colorectal cancer (CRC) are likely to have a recurrence within the first 1-2 years. Conventional imaging modalities have limitations in detecting recurrent disease early. The purpose of this study was to assess the usefulness of fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in the detection of recurrence in patients with CRCs. Methods One hundred and eighty-three patients, who were earlier treated with surgery and/or chemotherapy/radiotherapy, underwent 269 PET/CT studies for the detection of recurrence. The final diagnosis was made on the basis of histological analysis or clinical and imaging follow-up. Results The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value in detecting recurrent CRC using F-18-FDG-PET/CT were 87, 90, 88, 93, and 80%, respectively. PET/CT was found to have limitations in detecting microscopic disease and small-sized lesions. The common cause of false-positive PET/CT results was infective and inflammatory pathology in our setup. Conclusion PET/CT showed high sensitivity, specificity, and accuracy for the detection of recurrent disease in patients, who were earlier treated for CRC. PET/CT can be considered as a useful diagnostic tool in these patients. Nucl Med Commun 31: 590-596 (C) 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.