ESTRO 2025 - Abstract Book

S853

Clinical - Gynaecology

ESTRO 2025

Conclusion: EMBRACE-II provides detailed information about LNMs at diagnosis and individual nodal failures. The number of individual LNMs at diagnosis and the nodal regions affected are correlated with nodal control supporting the hypothesis of using a risk adapted treatment field approach.

Keywords: Cervical cancer, Lymph node metastases

References: [1] Peters, M. et al.; Risk factors for nodal failure after radiochemotherapy and image guided brachytherapy in locally advanced cervical cancer: An EMBRACE analysis. Radiother Oncol, 2021, 163: 150-158. [2] Nomden, C.N. et al.; Nodal failure after chemo-radiation and MRI guided brachytherapy in cervical cancer: Patterns of failure in the EMBRACE study cohort. Radiother Oncol, 2019, 134: 185-190.

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Digital Poster Prognostic impact and validation of new molecular classification in endometrial cancer patients Mehmet Varol 1 , Ilknur Gorken 1 , Goksenil Bulbul 2 , Emine Cagnur Ulukus 2 , Sefa Kurt 3 , Asli Akdoner 3 1 Radiation Oncology, Dokuz Eylul University, İzmir, Turkey. 2 Pathology, Dokuz Eylul University, İzmir, Turkey. 3 Obstetrics and Gynecology, Dokuz Eylul University, İzmir, Turkey Purpose/Objective: This article aims to evaluate the prognostic significance of the new molecular classification system in endometrial cancer (EC) patients and validate its clinical utility. By exploring its impact on patient outcomes, the study seeks to provide insights into its role in personalized treatment strategies. Material/Methods: The surgical specimens from 90 patients with stage I-III EC, who underwent surgery between 2014 and 2020, were reanalyzed using molecular techniques. Based on the results, molecular subgroups and risk groups were identified. Subsequently, overall survival (OS), progression-free survival (PFS), and local recurrence-free survival (LRFS) analyses were conducted. The impact of both the old and new classification systems on survival outcomes was assessed in conjunction with other prognostic markers. Results: The median follow-up time was 54.6 months (range: 10–100 months). Molecular subgroup analysis revealed that 4% of patients were PolE-mutated (PolEmut), 30% had Mismatch Repair Deficiency (MMRd), 13% were p53-mutated (p53abn), and 52% had No Specific Molecular Profile (NSMP). Risk group distributions based on the old and new classification systems were: low risk 36.6% and 37.8%; intermediate risk 13.3% and 21.1%; intermediate-high risk 12.2% and 15.6%; and high risk 37.7% and 25.6%, respectively. Seven-year survival rates for overall survival (OS), disease-free survival (DFS), and local recurrence-free survival (LRFS) were; 90.3%, 92.1%, and 95.2%, respectively. The new classification demonstrated a significant impact on OS (low or intermediate vs. intermediate-high or high risk, p=0.025). Additionally, TNM stage alteration (no change vs. upstaged), FIGO stage alteration (no change vs. upstaged), histologic type (endometrioid vs. non-endometrioid), tumor grade, lymph node metastasis (LNM), lymphovascular space invasion (LVSI), adjuvant treatment, and estrogen and progesterone receptor status significantly influenced OS, with respective p-values of 0.014, 0.016, <0.001, 0.001, 0.02, 0.027, 0.024, 0.001, and 0.007 in univariate analyses.