ESTRO 2025 - Abstract Book

S253

Brachytherapy - Gynaecology

ESTRO 2025

significant reduction of the number of implant needles for cervical brachytherapy shortened the duration of the procedure and it reduced trauma related morbidity, having less bleeding.

Conclusion: Interstitial approach can achieve local control while reducing normal tissue exposure. Applying on average 6 needles per fraction, might be a very good solution in order to cover the tumour volume while also protecting the surrounding organs, like rectum, sigmoid, bowel and bladder.

Keywords: interstitial brachytherapy, cervical cancer

References: 1. Sturdza AE, Knoth J. Image-guided brachytherapy in cervical cancer including fractionation. Int J Gynecol Cancer. 2022 Mar;32(3):273-280. 2. Smolic M, Sombroek C, Bloemers MCWM, van Triest B, Nowee ME, Mans A. Needle use and dosimetric evaluation in cervical cancer brachytherapy using the Utrecht applicator. Radiother Oncol. 2018 Mar;126(3):411-416. 3. Lombe D, Crook J, Bachand F, Moore J, Hamm J, Rose T, Anderson D, Batchelar D. The addition of interstitial needles to intracavitary applicators in the treatment of locally advanced cervical cancer: Why is this important and how to implement in low- and middle-income countries? Brachytherapy. 2020 May-Jun;19(3):316-322.

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Proffered Paper Image-guided adaptive brachytherapy in the treatment of primary vaginal cancer Harun Huskic, Alina Emiliana Sturdza, Johannes Knoth, Vincent Moritz Dick, Nicole Eder-Nesvacil, Joachim Widder, Christian Kirisits, Maximilian Schmid Christian Doppler Laboratory for Image and Knowledge Driven Precision Radiation Oncology, Department of Radiation Oncology, Medical University of Vienna / Vienna General Hospital, Vienna, Austria Purpose/Objective: To evaluate local control (LC), locoregional control (LRC), distant control (DC), overall survival (OS), and toxicity in patients with primary vaginal cancer treated with image-guided adaptive brachytherapy (IGABT) +/- external beam radiotherapy (EBRT) +/- concomitant chemotherapy (CCHT). Material/Methods: We retrospectively evaluated all patients with primary vaginal cancer treated with IGABT ± EBRT ± CCHT from 2000 to 2023 at one institution. Eligibility included histologically confirmed primary vaginal cancer (squamous cell, adeno-, or adenosquamous carcinoma) treated curatively with EBRT and IGABT or brachytherapy alone in selected cases. The high-risk clinical target volume (CTV-HR) for IGABT encompassed the macroscopic tumour at brachytherapy with an individualized margin. Kaplan-Meier analysis estimated LC, LRC, DC, and OS rates, while late toxicities were documented per CTCAE v5 criteria.

Results: 80 patients were included, characteristics are shown in Table 1.