Neutrophil–Lymphocyte Ratio and KELIM Score as Prognostic Markers in High-Grade Serous Advanced Ovarian Cancer Patients Treated with Neoadjuvant Chemotherapy

<b>Background/Objectives</b>: Advanced ovarian cancer (AOC) is frequently diagnosed at late stages, with a 5-year overall survival (OS) rate of approximately 25%. While primary debulking surgery followed by chemotherapy remains the standard treatment, neoadjuvant chemotherapy (NACT) followed by interval debulking surgery (IDS) is an alternative for patients with extensive disease. Achieving complete cytoreduction is a critical prognostic factor for OS and progression-free survival (PFS). This study evaluated the prognostic value of two biomarkers-the neutrophil-lymphocyte ratio (NLR) and the cancer antigen-125 (CA-125) ELIMination rate constant K (KELIM)-in predicting survival outcomes and recurrence rates in patients with AOC undergoing NACT. <b>Methods</b>: A retrospective, single-center analysis was conducted on 78 patients with high-grade serous AOC (stages III-IV) treated with platinum-based NACT followed by IDS between January 2013 and December 2023. NLR was calculated from prechemotherapy complete blood counts, with a threshold of ≥3 indicating elevated levels. KELIM, a marker of tumor chemosensitivity, was derived from CA-125 kinetics during the first 100 days of chemotherapy, with a cutoff of ≥1 denoting a favorable outcome. Clinical outcomes, including PFS and OS were analyzed using Kaplan-Meier survival curves, log-rank tests, and Cox regression models. <b>Results</b>: Results demonstrated that elevated NLR (≥3) and low KELIM (<1) were associated with poorer PFS and OS. KELIM score was identified as a strong prognostic marker for both PFS and OS, while NLR demonstrated weak association. Complete cytoreduction was achieved in 69.2% of patients, significantly correlating with improved survival outcomes. Postoperative complications, assessed using the Clavien-Dindo classification, were observed in a small subset of patients, with a total median hospital stay of 8 days. <b>Conclusions</b>: This study highlights the potential of NLR and KELIM as prognostic tools in AOC, aiding in patient selection for radical surgical interventions and predicting chemosensitivity. Future multicenter studies with larger cohorts are needed to validate these results and further explore the clinical utility of these biomarkers in optimizing treatment strategies for AOC.