P-178 Diffusion-weighted magnetic resonance imaging as an early predictive marker of chemoradiotherapy response in squamous cell carcinoma of the anus: An individual patient data meta-analysis

摘要: BackgroundPatients with squamous cell carcinoma of the anus (SCCA) are at risk of locoregional recurrence after chemoradiotherapy (CRT). An early prognostic marker of treatment response would enable timely individualisation of treatment for patients with SCCA. Diffusion-weighted (DW) magnetic resonance imaging (MRI) features, such as apparent diffusion coefficient (ADC), may be prognostic; however, few trials with small patient numbers exist for SCCA. Using an individual patient data meta-analysis, we aimed to investigate in a larger cohort whether ADC based histogram parameters from paired DW-MRI at baseline and during CRT correlate with local or any relapse in patients with SCCA.MethodsWe included 3 prospective trials, run between 2013 to 2017, in patients receiving radical CRT for SCCA who had paired DW-MRI at baseline and during week 2 of treatment in our individual patient data meta …