ESTRO 2023 - Abstract Book

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ESTRO 2023

Results The median follow-up time was 11.4 months. 5 patients (35.7%) and 9 patients (64.3%) were categorized as primary and recurrent disease, respectively. For primary cases, 2 patients were cervical cancer, and 3 patients were extramammary Paget’s disease of vulva. For recurrent cases, all patients were vaginal relapse, and the most common primary cancers were cervical cancer (44.4%), and ovarian cancer (33.3%). The median time to 3D-printed applicator brachytherapy for recurrent cases was 23.2 months. The mean dose of D90 HR-CTV for patients received external beam radiation followed by brachytherapy and brachytherapy alone was 85.3 Gy (EQD2) and 49.3 Gy (EQD2), respectively. At 3 months after treatment, 13 patients (92.9%) achieve complete response (CR) and 1 patient (7.1%) was considered partial response (PR). 1-year local relapse-free survival, distant metastasis-free survival, progression-free survival, and overall survival were 91.7%, 91.7%, 83.3% and 83.3%, respectively. The actuarial rate of grade 2 acute GU and GI toxicity were 7.1% for both. For late GU and GI toxicity, the actuarial rates were 7.1% and 14.3%, respectively. For skin and mucosa toxicity, there were 4 patients (28.6%) developed acute grade 3 toxicity, and 1 patient (7.1%) had persistent grade 3 vaginal toxicity.

Conclusion The treatment of IGABT by using 3D-printed applicators for HDR brachytherapy in difficult cases due to incompatibility of the applicators with patient’s anatomy or tumor demonstrated excellent outcomes and acceptable toxicity profiles.

PO-2152 Implementing a simple dose prediction tool to improve plan quality in cervical brachytherapy

E. Flower 1 , E. Sullivan 2 , G. Busuttil 2 , N. Thiruthaneeswaran 2 , J. Sykes 2 , A. Salkeld 2 , D. Thwaites 3 , J. Chard 2

1 Crown Princess Mary Cancer Centre , Radiation Oncology, Westmead, Australia; 2 Crown Princess Mary Cancer Centre, Radiation Oncology, Westmead, Australia; 3 University of Sydney, Institute of Medical Physics, Camperdown, Australia

Purpose or Objective