Role of carcinoembryonic antigen, magnetic resonance imaging, and positron emission tomography-computed tomography in the evaluation of patients with suspected local recurrence of colorectal cancer.

The role of carcinoembryonic antigen (CEA), magnetic resonance imaging (MRI), and positron emission tomography (PET)-computed tomography (CT) in detection of local recurrence of colorectal cancer is evaluated in 71 patients, selected due to suspected relapse at CT follow-up. Recurrence was confirmed by histology in 18 cases and excluded in 25 cases. Sensitivity, specificity, positive and negative predictive values, and accuracy were as follows: 44.4%, 92.5%, 66.7%, 83.1%, and 80.3% for CEA; 88.9%, 73.6%, 53.3%, 95.1%, and 77.5% for MRI; and 94.4%, 73.6%, 54.8%, 97.5%, and 78.9% for PET-CT. A diagnostic protocol integrating CEA and dedicated imaging studies is to be advocated.