Diagnostic value of integrated ¹⁸F-fluoro-2-deoxyglucose positron emission tomography/computed tomography in recurrent epithelial ovarian cancer: accuracy of patient selection for secondary cytoreduction in 134 patients

Abstract

Objective: The aim of this study was to evaluate the diagnostic value of integrated ¹⁸F-fluoro-2-deoxyglucose-positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) for suspected recurrence of epithelial ovarian cancer (EOC) with non-disseminated lesions.

Methods: We retrospectively reviewed the medical records of recurrent EOC patients who underwent secondary cytoreduction from January 2000 to December 2013. A total of 134 patients underwent secondary cytoreduction after imaging with either ¹⁸F-FDG-PET/CT or contrast-enhanced computed tomography (CECT).

Results: In a patient-based analysis of 134 patients, 124 (92.5%) were confirmed to be positive for malignancy. Among 72 patients with suspected non-disseminated recurrence on ¹⁸F-FDG-PET/CT, 65 (89.0%) were confirmed to have recurrence, giving 98.5% sensitivity, 87.7% accuracy, and 88.9% positive predictive value (PPV). In the 65 patients with recurrence, residual tumor remained in 14 patients, giving an accuracy of patient selection for secondary cytoreduction of 69.4% (50/72) and it is higher than that of CECT (64.0%). In 169 lesions removed from patients who underwent preoperative ¹⁸F-FDG-PET/CT, 135 (79.9%) were confirmed to be positive for malignancy and 124 were accurately detected by ¹⁸F-FDG-PET/CT, giving 91.9% sensitivity, 81.1% accuracy, and 85.5% PPV. Foreign body granuloma was found in 33.3% of 21 lesions with false-positive ¹⁸F-FDG-PET/CT findings (7/21). The mean preoperative cancer antigen 125 (CA-125) level in false-positive patients was 28.8 U/mL.

Conclusion: Compared with CECT, ¹⁸F-FDG-PET/CT shows higher sensitivity in lesion-based analysis and better accuracy of patient selection for secondary cytoreduction. However, there is still a need for integration of the results of ¹⁸F-FDG-PET/CT, CECT, and CA-125 levels to aid treatment planning.

Keywords: Cytoreduction Surgical Procedures; Granuloma, Foreign-Body; Ovarian Neoplasms; Positron Emission Tomography Computed Tomography.

Fig. 1

¹⁸F-FDG-PET/CT images of a 47-year-old women with stage IV papillary serous carcinoma of the ovary after a staging operation followed by chemotherapy with paclitaxel plus carboplatin for 12 cycles and radiation therapy to the left supraclavicular area. The preoperative CA-125 level before secondary cytoreduction was 8.4 U/mL. These images show a hypermetabolic nodule (maxSUV=7.2) in the right pelvic region (white or black arrows) suggestive of malignancy. After secondary cytoreduction, pathology confirmed foreign body granuloma in the lesion. This patient achieved complete remission with no recurrence for more than 5 years. ¹⁸F-FDG-PET/CT, ¹⁸F-fluoro-2-deoxyglucose-positron emission tomography/computed tomography; CA-125, cancer antigen 125; CT, computed tomography; maxSUV, maximum standardized uptake value; PET, positron emission tomography.