Clinical Usefulness of 18F-FDG PET/CT in the Detection of Early Recurrence in Treated Cervical Cancer Patients with Unexplained Elevation of Serum Tumor Markers

We investigated the diagnostic value of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) for restaging of treated uterine cervix squamous cell cancer with tumor maker elevation that was not explained by other conventional evaluation. We enrolled 32 cases who underwent PET/CT for the restaging of treated cervical cancer with tumor marker elevation that was not explained by recent conventional evaluation. All enrolled cases had squamous cell carcinoma. Increased tumor markers included squamous cell carcinoma antigen (SCC Ag) and carcinoembryonic antigen (CEA). PET/CT findings were determined by pathologic confirmation or clinical follow-up. We compared PET/CT accuracy and clinical parameters including normalization of tumor markers in both the SCC Ag elevation group and the CEA elevation group. The sensitivity, specificity, positive predictive value, and negative predictive value of PET/CT in detecting recurrence were 100%, 83.3%, 82.4%, and 100%, respectively. Accuracy was significantly different between the SCC Ag elevation group and the CEA elevation group (p=0.0169). PET/CT with SCC Ag elevation was more accurate (100%) than PET/CT with CEA elevation (66.7%). Normalization of tumor markers was observed more often in the SCC Ag elevation group than in the CEA elevation group (p=0.0429). PET/CT showed high negative predictive value and sensitivity in the restaging of cervical cancer with unexplained tumor marker elevation. PET/CT was more accurate in patients with SCC Ag elevation than in those with CEA elevation.