Expression of FOXM1 in G3 Neuroendocrine Tumors (NET G3) and G3 Neuroendocrine Carcinomas (NEC G3) of the Pancreas and the Intestine

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Introduction: G3 gastroenteropancreatic neuroendocrine tumors (G3 NET) and carcinomas (G3 NEC) differ considerably concerning their biological behavior and patients outcome. Whereas the WHO2017 classification for pancreatic NETs proposes a distinction of both groups using the Ki-67 proliferation marker (Klöppel et al. Reviews and Reports 2017), a useful marker for the subclassification of G3 intestinal NETs have not been recommended until now.

Aim(s): Forkheadbox protein M1 (FOXM1) is a crucial transcription factor in neoplastic cells and has been associated with tumor differentiation in gastrointestinal NETs (Briest et al. Oncotarget 2015). We therefore assessed FOXM1 as tumor marker to distinguish G3 NET from G3 NEC.

Materials and methods: Tumor specimens from 31 patients (26 NET G3 and 5 NEC G3) with complete histopathological and follow up data were studied immunohistochemically for FOXM1, Ki-67 and phospho-histone H3 expression.

Conference: 15th Annual ENETSConcerence (2018)

Presenting Author: Briest F

Authors: Briest F, Konukiewitz B, Anlauf M, Klöppel G, Grabowski P,

Keywords: gastroenteropancreatic neuroendocrine tumors, GEP-NET, NET G3, NEC G3, Tumor marker, FOXM1, Ki-67, differentiation,