Prediction of lymph node involvement in epithelial ovarian cancer by PET/CT, CT and MRI imaging

Objective: The aim of this study is to detect retroperitoneal metastatic lymph nodes in epithelial ovarian cancer with preoperative imaging methods (MRI, CT, 18F-FDG PET/CT). Material and method: Patients with epithelial ovarian cancer followed by the Akdeniz University Faculty of Medicine Gynecologic Oncology Surgery Department registered in the hospital’s electronic file system, who had undergone pelvic and/or paraaortic lymphadenectomy, and having undergone at least one imaging method (MRI, CT, PET/CT), were included in the study. Based on the data available, 89 patients were included in the study. Lymph node metastasis in the histopathology reports of these patients was accepted as the gold standard. The presence of lymph nodes on the imaging modalities (MRI, CT, PET/CT) was regarded as positive and was compared with the gold standard pathological lymph node metastasis. By doing so, the accuracy, specificity, sensitivity, PPV and the NPV of the imaging methods in predicting lymph node metastasis were calculated. Findings: Thirty-eight (42.7%) of 89 patients included in our study were at stage 3C. Based on the data, while 85 of the 89 patients included in the study obtained had undergone pelvic and paraaortic lymphadenectomy, four patients had undergone only pelvic lymphadenectomy. Of the patients, 73 had undergone a CT, 20 had undergone a PET/CT and 12 had undergone an MRI. The sensitivity, specificity, PPV, NPV and the accuracy of CT regarding all nodal involvement was 62%, 52%, 57%, 57%, and 57%, respectively. The PET/CT’s values were 63%, 66%, 70%, 60% and 65%, respectively. The sensitivity, specificity, PPV, NPV and the accuracy of PET regarding paraaortic nodal involvement alone were 50%, 91%, 80%, 73% and 75%, respectively. Conclusion: According to the data we obtained, it is challenging to decide whether to perform systemic pelvic and paraaortic lymphadenectomy based on imaging modalities (MRI, CT, PET/CT), and hence, further investigation is needed for more accurate imaging techniques.

PET/CT; MRI; CT; Lymphadenectomy; Ovarian cancer; Preoperative imaging

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