Multiparametric MRI assessment during cisplatin and trastuzumab therapy in esophageal adenocarcinoma xenografts

e15108 Background: Standard CT imaging is limited for determining neoadjuvant treatment response in esophageal cancer but there is increasing interest in assessing multiparametric MRI (mpMRI) in this role.We evaluated changes in mpMRI during Trastuzumab and Cisplatin therapy in a gastroesophageal adenocarcinoma xenograft model (OE19) expressing human epidermal growth factor receptor 2 (HER2). Methods: 3 groups of female severe combined immunodeficient mice (n = 15) were injected subcutaneously with 5x106 OE19 cells. Animals were treated with intraperitoneal (IP) saline twice a week (Control), Cisplatin 4mg/kg once a week (Group C) or Trastuzumab 20mg/kg twice a week (Group T) for a total of 2 weeks. Animals were scanned on a 9.4T MR imaging system (Bruker, Germany) at 3 time points: before (t0), 24 hours after first IP treatment (t1) and on completion of treatment (t2). Contrast-enhanced T1-weighted (T1w), T2-weighted (T2w), diffusion weighted (DW) and T2*-weighted (T2*) sequences were acquired. Early (t1...