Introduction/Background*Ovarian cancer is the leading cause of death from gynecologic cancer in the developed countries. (1)

Multimodality imaging approach with ultrasound, CT, MRI or PET/CT is often needed during the diagnosis and prior to the treatment. In AOC, a lot of studies have been done in order to demonstrate a better accuracy in staging advanced disease. Some studies showed PET/CT to be more accurate than traditional CT and MRI imaging, detecting LN metastases, extraabdominal disease and assessing equivocal findings in conventional imaging. (2–6)

Besides, a greater number of distant metastases will be found when using PET/CT as preoperative staging tool and many patients will be upgraded. (7–9).

The aim of this study was to compare the efficacy between preoperative PET/CT and ceCT findings according with the final pathology report in patients that underwent surgery for EOC treatment.

Methodology The study is a retrospective unicentric national observational study reviewing data of patients diagnosed with epithelial ovarian cancer that were operated as part of the treatment between July 2018 and February 2021, both included. PET/CT with ceCT started to be used routinely at hour hospital in 2018 for EOC patients. At our institution, the PET/CT is independently evaluated by two imaging specialists: a nuclear medicine doctor (PET-CT) and an expert radiologist in gyn malignancies who evaluate only the CT images.

Result(s)*56 patients were included in the final analysis. Sensitivity and specificity for PET/CT and CT were: 85% and 94.3% vs 80% and 94.3% in the ovarie; 38.1% and 91.2% vs 23.8% and 97.1% in the rectum; 50% and 86.7% vs 30% and 95.6% in the pelvic nodes; 33.3% and 97.1% vs 33.3% and 97.1% in the diaphragm; and 25% and 97.7% vs 25% and 100% in the small bowel mesentery.

When calculating PCI and comparing it to the surgery PCI, PET/CT showed a better intraclass correlation coefficient (0.856) than CeCT (0.751).

Conclusion*Both techniques showed a poor sensitivity and a very good specificity when comparing findings to surgery in the different anatomical places. However, when stimating PCI before surgery, PET/CT showed a better correlation with surgery than CeCT.