ESTRO 2025 - Abstract Book

S285

Brachytherapy - Gynaecology

ESTRO 2025

4570

Digital Poster Clinical Impact of Image-Guided Adaptive Brachytherapy in Locally Advanced Cervical Cancer: 5-Year Experience from a Developing Country Elena Manea 1,2 , Filip-Beniamin Zahapinschi 2 , Robert Teodorovici 2 , Ionel Bolohan 2 , George Cristian Mihaila 3 1 Radiotherapy Department, “Gr. T. Popa” University of Medicine and Pharmacy, Iasi, Romania. 2 Radiotherapy Department, Regional Institute of Oncology, Iasi, Romania. 3 Radiotherapy Department, Bacau County Emergency Hospital, Bacau, Romania Purpose/Objective: This study aims to evaluate the clinical impact of IGABT in the management of LACC in a resource-constrained setting over five years. Material/Methods: 102 consecutive pts with LACC treated with chemo-radiotherapy and high dose rate (HDR) IGABT from April 2018 – October 2023 were included. Pts received external beam radiotherapy (EBRT) including nodal boost sequentially/Simultaneous Integrated Boost (SIB) +/- concomitant chemotherapy and HDR IGABT. The high-risk CTV (CTV HR ), intermediate-risk CTV (CTV IR ), organ at risks (bladder, rectum, sigmoid, and bowel) contouring and treatment planning respected European Brachytherapy European Society for Radiation Oncology (GEC-ESTRO) recommendations. Cumulative doses were calculated using the linear-quadratic model (EQD 2 ). The goal of overall treatment time (OTT) was under 50 days. The follow-up was performed every three months for the first two years and six months thereafter. The toxicity was examined as occurrence of late morbidity assessed using Common Terminology Criteria for Adverse Events. Statistical analyses were used to investigate clinical and dosimetric predictors of toxicity. The clinical outcomes, including local control, disease-free survival (DFS), overall survival (OS), and treatment-related toxicities, were assessed. Results: The median age of the pts was 58 years. Stage IIB, IIIC1r, IIIC2r and IVA were 32 pts, 53 pts, 13 pts and IVA, respectively. The mean D 90 for the CTV HR and CTV IR were 84 Gy and 66 Gy. Median doses to D 2cc of the bladder, rectum, sigmoid, and small bowel were 81.5 Gy, 67.7 Gy, 65.5 Gy, and 61 Gy, respectively. Median doses of D 0.1cc for bladder, rectum, sigmoid, and small bowel were 98.8 Gy, 75.1 Gy, 74.3 Gy and 65.5 Gy, respectively. 73 pts respected OTT. Median follow-up was ~60 months. After the treatment, 91.8 % achieved locoregional remission. Genitourinary (GU) and gastrointestinal (GI) morbidity were 14.38% and 12.56%. 22.3% presented grade 2-3 late morbidity. The overall rate of GU adverse event grade 1 was 4.9% (n=5) and >grade 2 was 5.15% (n=6). D 2cc bladder ≥80 Gy (EQD 2-3 ) was 5 of the 6 pts. The overall rate of GI adverse events>grade 2 was 12.08% (n=11). D 2cc rectum ≥65 Gy had 7 of the 11 pts and 6 had D 2cc sigmoid ≥65 Gy. The 5-year overall survival (OS) rate was 75%, while the 5-year disease-free survival (DFS) rate was 68%. The local control rate at 5 years was 80%. Conclusion: IGABT is proving to be a feasible and beneficial modality, improving patient outcomes and quality of life, despite the challenges of implementing advanced radiotherapy techniques in a developing.

Keywords: Cervical cancer, brachytherapy