The Role of 18F-FDG PET/CT in Detecting Ovarian Cancer Recurrence in Patients with Elevated CA-125 Levels

Abstract

Objectives: To investigate the role of 18F-FDG positron emission tomography/computed tomography (PET/CT) in detection of recurrence in ovarian cancer patients with increased CA-125 levels. Methods: Fifty-two patients (30-80 years old, mean: 58.5±10.6 years) who had been histopathologically diagnosed with ovarian cancer, underwent 18F-FDG PET/CT imaging for re-staging due to elevation of CA-125 levels were included in this retrospective study. 18F-FDG PET/CT findings were compared with histopathological, radiological and clinical follow-up results. Results: CA-125 levels ranged between 35.2-2740 U/mL (N: 0-35 U/mL). Recurrent disease was detected in 45 of 52 patients on PET/CT imaging. There were three false negative and one false positive result. In addition to abdominal and pelvic lesions, 14 distant metastatic lesions (brain, lung, liver and bone metastasis) were identified correctly on PET/CT imaging. Sensitivity, specificity, positive and negative predictive value and accuracy of 18F-FDG PET/CT were calculated as 94%, 75%, 98%, 50% and 96%, respectively. Conclusion: 18F-FDG PET/CT is a useful imaging method that can be used in detection of ovarian cancer recurrence in patients with elevated CA-125 levels. Since this modality offers whole body imaging, distant metastases could be detected in addition to abdominal and pelvic lesions thus contributing to patient management.