Introduction/Background The objective of this study was to assess the value of preoperative PET/CT scan,combined with clinical variables, in predicting complete resection in highly pre-selected patients operated in centers with high rate of complete resection.

Methodology This multicentric, observational, retrospective study evaluated ovarian cancerpatients who underwent primary cytoreductive surgery for advanced ovariancancer in two Spanish centers between January 2017 and January 2022. AllPET/CT were reviewed, and a modified PCI score was calculated. Clinicalvariables and preoperative findings in the PET/CT were analyzed and amultivariate model was built. A predictive value score based on the OR of thevariables was constructed.

Results 45 patients underwent upfront primary cytoreductive surgery. The completeresection rate was 80% (36 patients).On multivariate analysis, 2 clinical variables and 2 preoperative PET/CT findingswere associated with no-complete resection surgery: Presence ofextraabdominal lymph node, modified PCI value of 6 or more, Age 58 years andASA score 3. The predictive score value of each variable was 11, 2, 2 and 1,respectively.For this multivariate model predictive of non-complete cytoreduction, the AUCwas 0.881. A predictive value of 5 or more was the most predictive cutoff fornon-complete cytoreduction. Complete resection rate was 91.7% in patientswith a score of 4 or less and 33.3% in patients with 5 or more points in thepredictive value score.

Conclusion In highly pre-selected cohorts of patients, a predictive score value can beconsider as a cut-off for sending patients to neoadjuvant chemotherapy.