Abstract 5773
Background
Anal Squamous Cell Carcinoma (ASCC) is radically treated by chemoradiotherapy (CRT). The use of DW-MRI as a predictive marker of outcome would enable early individualisation of treatment. We aimed to quantify the changes in mean apparent-diffusion-coefficient (ADCMean) between a DW-MRI at diagnosis and on fraction 8-10 of CRT as a biomarker for cellularity, and correlate these with outcome.
Methods
This prospective study recruited patients with ASCC between October 2014 and November 2017. DW-MRI was performed at diagnosis and after fraction 8-10 of radical CRT. A region of interest (ROI) was delineated for all primary tumours and any lymph nodes >2 cm on high-resolution T2 –weighted images and propagated to the ADC map. A pre-defined cut-off for percentage change in ADCMean (ΔADC) was set at < 20%. Complete response (CR) was assessed 3 months following completion of CRT. Routine clinical follow up data from patients were collected from NHS electronic systems.
Results
Twenty-three of 29 recruited patients underwent paired DW-MRI scans. The median (range) tumour volume was 13.6 cm3 (2.8 cm3 to 84.9 cm3). The median ΔADCMean between scans was 20.7% (95% CI: 12.7%, 34.1%). Nine of 23 (43%) patients had a change of ADCMean <20%. Two patients failed to achieve a CR, with ΔADCMean of 14.6% and 20.3%, respectively. On routine follow up, 2 further patients had relapsed, with ΔADCMean of -1.2% and 6.8%.
Conclusions
In a subset of patients, <20% ΔADCMean on DW-MRI between diagnosis and day 8-10 of CRT was observed. Four patients in the study demonstrated persistent or recurrent disease, all of whom demonstrated an ADC on or below the pre-specified cut-off. Further investigation of the predictive merit of DW-MRI change, and the optimum cut-off is needed in larger cohorts.
Clinical trial identification
NCT02145416.
Editorial acknowledgement
Legal entity responsible for the study
University of Oxford.
Funding
CRUK EPSRC Cancer Imaging Centre in Oxford, the CRUK Oxford Centre and the NIHR.M Hawkins is supported by Medical Research Council grant MC_UU_00001/2.
Disclosure
R. Muirhead: Honoraria (self), Fee for lecture: Boehringer Ingelheim. V. Goh: Research grant / Funding (self): Siemens. All other authors have declared no conflicts of interest.
Resources from the same session
5203 - Novel fusion genes identified from matched primary and recurred breast cancers by RNA-sequencing
Presenter: Soojeong Choi
Session: Poster Display session 2
Resources:
Abstract
5873 - Association between PIK3CA mutation status and development of brain metastases in HR+/HER2- metastatic breast cancer
Presenter: Donna Fitzgerald
Session: Poster Display session 2
Resources:
Abstract
3588 - The role of AXL as mechanism of resistance to trastuzumab and a prognostic factor in breast cancer HER2 positive: a translational approach.
Presenter: Anna Adam-Artigues
Session: Poster Display session 2
Resources:
Abstract
5640 - Untargeted assessment of tumor fractions in plasma for monitoring and prognostication from metastatic breast cancer patients undergoing systemic treatment
Presenter: Marija Balic
Session: Poster Display session 2
Resources:
Abstract
2616 - Clinical application of mutational analysis in breast cancer patients: the relevance of PIK3CA analysis for precision medicine.
Presenter: Juan Miguel Cejalvo
Session: Poster Display session 2
Resources:
Abstract
3870 - A retrospective gene expression analysis of surgically-removed Breast Cancer Brain Metastasis (BCBM)
Presenter: Meritxell Mallafré-Larrosa
Session: Poster Display session 2
Resources:
Abstract
1240 - Endocrine therapy alone versus targeted combination strategy as first line treatment in elderly patients with hormone receptor-positive advanced breast cancer: meta-analysis of Phase II and III randomized clinical trials
Presenter: Claudia Omarini
Session: Poster Display session 2
Resources:
Abstract
5535 - Alpelisib (ALP) + fulvestrant (FUL) for patients with hormone receptor–positive (HR+), HER2− advanced breast cancer (ABC): management and time course of key adverse events of special interest (AESIs) in SOLAR-1
Presenter: Hope Rugo
Session: Poster Display session 2
Resources:
Abstract
3093 - Changes in Hormone-Receptor status in Luminal breast cancers between primary tumor and metastases: results of the observational cohort GIM-13 AMBRA Study
Presenter: Marina Cazzaniga
Session: Poster Display session 2
Resources:
Abstract
1378 - MONARCH 3: Updated time to chemotherapy and disease progression following abemaciclib plus aromatase inhibitor (AI) in HR+, HER2- advanced breast cancer (ABC)
Presenter: Miguel Martín
Session: Poster Display session 2
Resources:
Abstract