Role of 18F-FDG PET/CT in detecting pelvic lymph-node metastases in patients with early-stage uterine cervical cancer: comparison with MRI findings

Abstract

Objective: This study aimed to investigate the applied value of F-fluoro-2-dexoxyglucose (F-FDG) PET/computed tomography (CT) and MRI in detecting lymph-node metastasis in early-stage cervical cancer.

Materials and methods: A retrospective study was performed on 87 early-stage cervical cancer patients evaluated with PET/CT and pelvic MRI before surgery. Histopathological evaluation of lymph nodes served as the diagnostic standard. F-FDG PET/CT and MRI images were analyzed and correlated with histopathological findings.

Results: The overall node-based sensitivity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET/CT were 91% (61/67), 78.2% (61/78), 99.4% (1079/1085), and 98% (1140/1163), respectively, which were higher than the corresponding values of MRI, at 37.3% (25/67), 61% (25/41), 96.3% (1080/1122), and 95% (1105/1163) (P<0.034). The difference in diagnostic efficacy for identifying node-based metastases between PET/CT and MRI was significant (PET/CT vs. MRI, 0.719 vs. 0.587, P=0.017). Meanwhile, the overall patient-based sensitivity, PPV, NPV, and accuracy of PET/CT were 100% (34/34), 87.2% (34/39), 100% (48/48), and 94.3% (82/87), respectively, whereas the corresponding MRI values were 44% (15/34), 65% (15/23),74% (45/61), and 69% (60/87) (P<0.04). The difference in diagnostic efficacy for identifying patient-based metastases between PET/CT and MRI was significant (PET/CT vs. MRI, 0.974 vs. 0.705, P<0.001).

Conclusion: PET/CT has been proven to be valuable in detecting lymph-node metastases. Compared with MRI, PET/CT has higher sensitivity, PPV, NPV, and accuracy in patients with early-stage cervical cancer for detecting lymphatic metastases.