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
5063 - Does Nutritional Status Affect Treatment Tolarability, Response and Survival in Metastatic Gastric Cancer Patients? Results of Prospective Multicenter Study
Presenter: Senem Karabulut
Session: Poster Display session 2
Resources:
Abstract
2717 - Ramucirumab use in patients with Advanced Gastric Cancer (AGC) or gastro-oesophageal junction (GEJ) adenocarcinoma in Spain: RAMIS observational study
Presenter: Federico Longo Munoz
Session: Poster Display session 2
Resources:
Abstract
3187 - Gastrectomy plus chemotherapy versus chemotherapy alone for advanced gastric cancer with a single non-curable factor: Exploratory analysis in the patients who were enrolled in JCOG0705/KGCA01 phase III trial (REGATTA) and could continue chemotherapy
Presenter: Takaki Yoshikawa
Session: Poster Display session 2
Resources:
Abstract
4765 - A prospective observational study on the optimal maintenance strategy in HER2-positive advanced gastric cancer treated with trastuzumab based therapy
Presenter: Qian Li
Session: Poster Display session 2
Resources:
Abstract
3500 - Randomised phase 2 trial of first-line docetaxel, carboplatin, capecitabine (CTX) and epirubicin, oxaliplatin, capecitabine (EOX) in advanced esophagogastric adenocarcinoma (SEED)
Presenter: Peter Petersen
Session: Poster Display session 2
Resources:
Abstract
5197 - Ramucirumab in the treatment of refractory metastatic gastric cancer: results from the RamSelGa trial.
Presenter: Alexey Tryakin
Session: Poster Display session 2
Resources:
Abstract
2011 - Regorafenib in combination with Paclitaxel for beyond first-line treatment of advanced esophagogastric cancer (REPEAT): a phase Ib trial with expansion cohort
Presenter: Mohammed Khurshed
Session: Poster Display session 2
Resources:
Abstract
2117 - The relationship between the survival and fixed dosing of S-1 in advanced gastric cancer patients by pooled analysis using individual data from four Japanese randomized phase III trials
Presenter: Wataru Ichikawa
Session: Poster Display session 2
Resources:
Abstract
2669 - A Phase 1b Study of Oraxol in Combination with Ramucirumab in Patients with Gastric or Esophageal Cancers who failed previous chemotherapy
Presenter: Ming Huang Chen
Session: Poster Display session 2
Resources:
Abstract
3240 - Efficacy and safety of trifluridine/tipiracil (FTD/TPI) in European patients with heavily pretreated metastatic gastric cancer (mGC): an analysis of the TAGS study
Presenter: Maria Alsina
Session: Poster Display session 2
Resources:
Abstract