ESTRO 2024 - Abstract Book

S212

Brachytherapy - Gynaecology

ESTRO 2024

between 45-50.4 Gy along with concurrent chemotherapy (CCRT). HDR-BT (24 Gy) was prescribed to a high-risk clinical target volume (HR-CTV).

Results:

139 patients were included and HDR-BT program could be fully performed in 136 patients (98%). Over a median follow-up duration of 40.5 months, the two-year local control (LC), overall survival (OS), and disease-free survival (DFS) rates stood at 79.4%, 77.7%, and 61.7% respectively, with five-year rates at 78.2%, 61.6%, and 55.7%. Multivariate analysis revealed the primary determinant of LC as the tumor's response to external beam radiotherapy (EBRT) as determined via magnetic resonance imaging (MRI) prior to BT. Parametrial involvement demonstrated a significant multivariate association with DFS (p = 0.04). Regarding OS, parametrial invasion (p = 0.01) and the tumor's response post-chemoradiotherapy (p = 0.02) emerged as significant factors. Regarding chronic toxicities, 18% (25 patients) experienced grade 3 complications. An optimal D2cc (Bowel) threshold of 70 Gy (p = 0.001) was identified to limit chronic digestive complications of grade 3 or higher.

Conclusion: