Systematic Evaluation of the Immune Microenvironment of Neuroendocrine Tumors (NET) Abstract #2199

Introduction: Immunotherapy is being explored in many tumour types with encouraging results, but its role in the management of NET is yet to be defined.
Aim(s): Here we characterise the immune landscape of NET in order to inform a rational approach for immunotherapy in this patient group.
Materials and methods: Peripheral blood and fresh tissue (tumour and normal) were collected from consenting patients undergoing surgical resection for midgut NET. Multicolour flow-cytometry was performed to determine the abundance of CD8+, CD4+FoxP3- effector (CD4eff) and CD4+FoxP3+ regulatory (Treg) T cell subsets, and the expression of co-inhibitory and co-stimulatory checkpoint molecules. Matched tissue was obtained for immunohistochemistry (IHC) to investigate the geographical distribution of the immune infiltrate.
Conference: 15th Annual ENETS conference (2018)
Category: Basic Science - Signaling pathways, receptors, biomarkers
Presenting Author: Dr Clare Vesely

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