ESTRO 2025 - Abstract Book

S792

Clinical - Gynaecology

ESTRO 2025

Conclusion: Despite better dose conformality of VMAT and the use of BMS, but with 55.6% extended field radiotherapy in the BMS VMAT group, blood cell counts were similar between BMS VMAT and non-BMS 3DCRT/IMRT in women with LACC. In all women the immune system was suppressed compared to baseline. However, immune cell function data will follow. Stricter BMS or advanced techniques including proton therapy might lead to improvement.

Keywords: immune system,cervical cancer,bone marrow sparing

References: [1] Van Meir H, Nout R, Welters M, Loof N, De Kam M, Van Ham J, et al. Impact of (chemo) radiotherapy on immune cell composition and function in cervical cancer patients. Oncoimmunology. 2017;6:e1267095 [2] Corbeau A, Nout RA, Mens JWM, Horeweg N, Godart J, Kerkhof EM, et al. PROTECT: prospective phase-II-trial evaluating adaptive proton therapy for cervical cancer to reduce the impact on morbidity and the immune system. Cancers. 2021;13:5179 [3] Corbeau A, Kuipers SC, de Boer SM, Horeweg N, Hoogeman MS, Godart J, et al. Correlations between bone marrow radiation dose and hematologic toxicity in locally advanced cervical cancer patients receiving chemoradiation with cisplatin: a systematic review. Radiotherapy and Oncology. 2021;164:128-37

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Digital Poster Stereotactic Body Radiation therapy (SBRT) with MRI-Linac in oligometastatic gynaecological cancer patients: a systematic review Donato Pezzulla 1 , Alessia Re 2 , Francesco Catucci 2 , Martina Iezzi 2 , Savino Cilla 3 , Davide Cusumano 4 , Gabriella Macchia 1 , Francesco Preziosi 2 , Gian Carlo Mattiucci 2,5 , Francesco Deodato 1,5 1 Radiation Oncology Unit, Responsible Research Hospital, Campobasso, Italy. 2 UOC Radioterapia Oncologica, Mater Olbia Hospital, Olbia, Italy. 3 Medical Physics Unit, Responsible Research Hospital, Campobasso, Italy. 4 Unit of Medical Physics, Mater Olbia Hospital, Olbia, Italy. 5 Istituto di Radiologia, Università Cattolica del Sacro Cuore, Roma, Italy Purpose/Objective: This review aims to provide a comprehensive overview of the current evidence on the use of MR-guided SBRT (MRgSBRT) for oligometastases in gynecologic cancers and its potential benefits. Material/Methods: This systematic review, conducted per PRISMA guidelines, evaluated studies on MRI-Linac SBRT in treating oligometastatic gynecological cancer. A MEDLINE search (January 2000–March 2024) identified 475 scientific articles using terms related to MRI-Linac, SBRT, and gynecologic metastases. Eligible studies included full-text articles in English reporting outcomes and toxicity. Results: Only three studies (2021-2022) could be selected [1-3], comprising one case report, one Phase 1 trial, and one retrospective study. They involved 45 patients with oligometastatic gynecologic cancers, predominantly ovarian, treated with MRI-Linac SBRT: 7 lesions were treated with a 1.5T MRI linac, while the remaining 17 ones were treated with a 0.35T. Doses ranged from 30 to 50 Gy over five fractions. Information on treatment time was reported only in two experiences [1-2]: Cuccia reported a time of 37 minutes (26-81), while Henke outlined the time spent on the table for patients who required replanning and who did not, noting that the average time was 73+16 minutes for the first group and 56+18 minutes for the second. Toxicity profile was available in all the studies, showing favorable results, with only one reported Grade 3 event, underscoring a favorable safety profile. Focusing on actuarial outcome, all the patients were alive and maintained local control at three months from SBRT. However, only in two