Application and Indication of Carcinoembryonic Antigen Triggered 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Scanning in the Detection of Relapse of Colorectal Cancer Patients After Curative Therapy
This study aimed to explore the characteristics of patients with colorectal cancer (CRC) following curative therapy that may benefit from fluorine-18-2-uoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) scanning, evaluate the application of carcinoembryonic antigen (CEA)–triggered 18F-FDG PET/CT scanning, and provide referential indicators.Methods
This retrospective study included 56 CRC patients who received a PET/CT scan as a primary examination because of rising CEA levels after curative therapy and who had not received any other radiological examinations previously.Results
The rate of recurrence or metastasis was 75.0% by PET/CT scan but was 69.6% with follow-up treatment. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 94.9%, 70.6%, 87.5%, 88.1%, and 85.7%, respectively. TNM (tumor, node, metastasis) stage, body mass index, and CEA level were significant prognostic factors.Conclusions
Positron emission tomography/CT can be selectively applied as a primary examination in CRC patients with asymptomatic elevation of CEA. High CEA levels, increased body mass index, and advanced TNM staging are risk factors for relapse.