Application of Multimodal Imaging Biomarker in the Differential Diagnosis of Ovarian Mass: Integration of Conventional and Molecular Imaging.

The aim is to investigate the diagnostic performance of multimodal imaging with 18F-FDG PET/CT, MRI, and contrast-enhanced CT (CECT) in cases with unilateral or bilateral ovarian mass without ancillary findings of malignancy.Retrospectively, 307 patients who had unilateral or bilateral ovarian masses and underwent preoperative FDG PET/CT and/or MRI/CECT were included. The criterion standard for the ovarian mass was the final pathology. The peak standardized uptake value (SULpeak) among benign tumors (BTs), borderline ovarian tumors (BoTs), and malignant ovarian tumors (MTs) were compared. The cutoff value of SULpeak to discriminate between BT/BoT and MT was determined from the training (n = 200) and validation (n = 131) cohorts. Diagnostic performances of SULpeak, Ovarian-Adnexal Reporting Data System (O-RADS) MRI score, CECT findings, and combination of multimodal imagings were analyzed.SULpeak of MT was significantly higher than that of BT or BoT (P < 0.05). There was no significant difference in SULpeak between BT and BoT (P = 0.147). The cutoff value of SULpeak for discriminating between BT/BoT and MT was 1.76 (sensitivity, 87.0%; specificity, 83.0%). Diagnostic performance for BT/BoT versus MT of O-RADS MRI, CECT, FDG PET/CT plus O-RADS MRI score, and FDG PET/CT plus CECT yielded the respective sensitivities of 100%, 94%, 95%, and 82%, and specificities of 43%, 46%, 88%, and 91%, respectively.Multimodal imaging biomarkers including FDG PET/CT and MR/CECT could provide additional information to differentiate ovarian masses.