Tumor immune microenvironmental characteristics in Human Epidermal Growth Factor-2 (HER2) positive esophageal adenocarcinoma: a comparative analysis and biomarker study

84 biopsies were taken from the TRAP cohort (neoadjuvant chemoradiotherapie according to CROSS with trastuzumab and pertuzumab; n=40, HER2+ n=40), and a control cohort with neoadjuvant chemoradiotherapy only (n=44; HER2+ n=4) before treatment. Eventually, 83 biopsies were eligible for analyses following quality-control; biopsies were analysed using targeted gene expression analysis (Nanostring) with the immune-oncology panel (750 genes). These results allowed to chart the tumor-immune microenvironmental characteristics of HER2 positive tumors in patients with esophageal adenocarcinoma. Case-control study