ESTRO 2024 - Abstract Book

S991

Clinical - Gynaecology

ESTRO 2024

This is a retrospective analysis of fourteen patients from 2007 to 2022 with locally advanced endometrial cancer with cervical and/or parametrial involvement treated with neoadjuvant external beam radiotherapy (45-50.4 Gy in 25 to 30 fractions) and conventional high-dose rate brachytherapy (5.5-7.0 Gy per fraction in 3 to 4 fractions) followed by extrafascial hysterectomy at our center. Clinical data, pathologic response and survival outcomes were evaluated. Possible factors associated with pathologic response were analyzed.

Results:

Majority of the patients presented with stage III disease (86%), with all patients having clinical cervical extension. Additionally, 93% had parametrial involvement and 14% had nodal involvement. 86% received chemotherapy either concurrently or adjuvantly. Post-surgery evaluation revealed no pathologic cervical involvement in 86% and negative surgical margins in 93% of cases. Pathologic complete response was observed in 43%. Two patients (14%) experienced locoregional recurrence. With a median follow-up period of 30 months, the recurrence-free survival and overall survival rates were 86% and 100%, respectively. Correlation analyses revealed a significant association between lower grade tumors and pathologic complete response (Φ=0.72, p=0.026). No significant correlation was found between pathologic complete response and other factors including age, stage, tumor size, nodal involvement, histology, equivalent dose, radiotherapy technique and time between radiotherapy and surgery. No late grade 3-4 toxicities were recorded.

Conclusion:

Neoadjuvant radiation, comprising external beam radiotherapy and conventional HDR brachytherapy, followed by hysterectomy with or without chemotherapy, is a viable option for managing endometrial cancer patients with extension to the cervix and/or parametrium. This approach may enhance resectability, resulting in high rates of pathologic complete response and negative resection margins. These findings suggest the potential effectiveness of this treatment strategy for this challenging patient population.