ESTRO 2024 - Abstract Book

S981

Clinical - Gynaecology

ESTRO 2024

References:

1. Horeweg N, Nout RA, Jurgenliemk-Schulz IM, Lutgens LCHW, Jan J. Jobsen M, Haverkort MAD, et al. Molecular Classification Predicts Response to Radiotherapy in the Randomized PORTEC-1 and PORTEC-2 Trials for Early Stage Endometrioid Endometrial Cancer. J Clin Oncol. 2023;

2. Getz G, Gabriel SB, Cibulskis K, Lander E, Sivachenko A, Sougnez C, et al. Integrated genomic characterization of endometrial carcinoma. Nature. 2013;497(7447):67–73.

369

Poster Discussion

Outcomes following complete response on MRI following radical chemoradiotherapy for cervical cancer

Stephanie Anderson, Ailsa Gemmell, Rufus Turner, Claire Duncanson, Ashleigh Kerr, Rosie Harrand, Azmat Sadozye, Kathryn Graham

Beatson West of Scotland Cancer Centre, Clinical Oncology, Glasgow, United Kingdom

Purpose/Objective:

Radical chemoradiotherapy (CCRT) is the standard of care for locally advanced cervical cancer. Incorporating state of the art image-guided brachytherapy (IGBT) has led to significant improvements in outcomes. Data from the EMBRACE-1 trial indicate that achieving a minimum 90% of 85Gy to the high-risk CTV (CTV HR ) volume will result in local control rate of 95% at 3-years in squamous cell tumours [1]. Contemporary studies including EMBRACE-1 typically mandate 3-month and 12-month MRI to assess response, but there is no agreed UK or European recommendation on optimal imaging modality and/or timing post treatment. Some centres utilise PET-CT although this may not be cost effective and an early complete metabolic response does not preclude relapse especially in high risk disease. Notably, over 90% of patients achieved complete remission on MRI at 3 months post treatment in EMBRACE-1 and there was no detrimental impact on outcomes if resolution occurred at up to 6-9 months [1]. The West of Scotland Cancer Network (WOSCAN) provides oncology input to almost half of the Scottish population. Approximately 80 patients with locally advanced cervical cancer will receive radical CCRT annually, many of whom are from a socio-economically deprived background and present with very bulky disease. Our practice consists of intensity modulated radiotherapy (IMRT) to the pelvis followed by IGBT, utilising a ring and tandem applicator. CT is incorporated to outline the organs at risk, but prescription is to the traditional point A rather than the GYN GEC ESTRO CTV HR guideline. We also consider neoadjuvant chemotherapy (up to 6 cycles of 3-weekly carboplatin/paclitaxel for primary tumours ≥5cm and/or the presence of multiple or para-aortic nodes).

Here, we describe radiological outcomes on MRI at 3 months post CCRT and corresponding disease control rates.

Material/Methods:

The central radiotherapy prescribing system at WOSCAN was interrogated to identify patients who commenced radical RT/CCRT for cervical cancer, 1st January 2017 to 31st December 2019 inclusive. Exclusion criteria consisted of prior hysterectomy, and/or RT/CCRT delivered in the adjuvant or salvage settings. Clinico-pathological data and