Immune landscape in mixed neuroendocrine-non neuroendocrine neoplasms (MiNEN)

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Introduction: A mixed neuroendocrine-non neuroendocrine neoplasm (MiNEN) is a novel defined rare entity, made up of two morphologically distinct neoplastic components; one neuroendocrine type (NEN), and the other one non-neuroendocrine type (nNEN). Neuroendocrine differentiation of tumors is thought to influence the tumor microenvironment (TME) through the secretion of various hormones or growth factors.

Aim(s): The aim is to characterize the TME by evaluating the status of both tumor components in 18 cases of MiNENs.

Materials and methods: To analyse the dynamics of the MiNENs TME, IHC expression of CD3+, CD8+, Foxp3+ and Grzb+ lymphocyte subpopulations (TILs) were evaluated in the two components. TILs counting was determined by digital pathology, considering the number of positive cells for area (200x). Furthermore, in order to verify the balance between cytotoxic (CT) and immunosuppressive (IS) activity in the TME, we simultaneously quantified by multiplex immunofluorescence the expression of Foxp3/CD8 (IS) and Grzb/CD8 (CT).

Conference:

Presenting Author:

Authors: Di Mauro A, Ferrara G, Iervolino D, Scognamiglio G, Clemente O,

Keywords: mixed neuroendocrine, neuroendocrine, tumor microenvironment, immunotherapy, biomarker,