972 Relationship between KELIM score and perioperative outcomes during interval debulking surgery after neoadjuvant chemoteraphy in advanced ovarian cancer

Introduction/Background Neoadjuvant chemotherapy (NACT) followed by interval debulking surgery is a treatment option for advanced ovarian cancer (AOC) when primary debulking surgery is not feasible because of patient status or extent of disease. The modulated CA-125 elimination rate constant (KELIM) has been associated with chemosensitivity. The aim of this study is to investigate the association between KELIM and perioperative parameters. Methodology Retrospective cohort study including all newly AOC diagnosed between January 2021 -December 2022 at Trueta University Hospital. KELIM score was calculated using three CA-125 determinations during the first 100 days of neoadjuvant chemotherapy. Data was retrieved from prospective maintained data base of our unit. Patients were categorized in two groups: favourable (>=1) and unfavourable (Results During the period of study, 80 patients were diagnosed with AOC, 42 of them were not amenable for upfront surgery and were treated with neoadjuvant chemotherapy. Of them, 34 (81%) had unfavourable KELIM score, and in only 6 patients (14.3%) KELIM score was favourable. In 2 cases (4.8%), there were not enough CA-125 values to determinate KELIM score. PCI (Peritoneal Carcinomatosis Index) was higher in unfavourable KELIM score (16.08 vs 7.00), which results in statistically significant difference. Nevertheless non others parameters were significant. In Table 1 perioperative results according to KELIM score are shown. Conclusion In our cohort of patients treated with neoadjuvant chemotherapy, unfavourable KELIM score was much more frequent than favourable, showing that the cohort of patients allocated to neoadjuvant chemotherapy is a cohort of poor prognosis patients. PCI was higher in unfavourable KELIM score. However, we couldn't demonstrate significant differences in major complications, surgical complexity score or delay to restart chemotherapy. Disclosures No relevant or material financial interests influenced the research described in this article.