Even Malignant Appendiceal Neuroendocrine Tumors Exhibit No Recurrent Chromosomal Alterations

#1490

Introduction: Neuroendocrine tumors (NETs) of the midgut are located in the ileum (iNET), caecum or appendix (aNET). Despite of the similar origin, NETs of the ileum and the appendix behave remarkably different. iNETs show high malignant potential, which manifests with early lymph node or liver metastases. Genetically, the loss of chromosome 18 (Ch18) in 60-74% of cases is the most frequent alteration in iNETs. aNETs are often incidental findings, rarely show metastases, and no chromosomal alterations are known.

Aim(s): We addressed the question whether aNETs harbor chromosomal aberrations which are possibly related to malignant behavior.

Materials and methods: We analyzed chromosomal copy number (CN) variations in 7 nodal positive and 8 nodal negative formalin-fixed paraffin-embedded aNETs using the OncoScan assay (Affymetrix). Fluorescence in-situ Hybridization (FISH) with a Ch18-centromer probe was carried out on tissue microarrays containing 45 aNETs.

Conference: 13th Annual ENETSConcerence (2016)

Presenting Author: Sipos B

Authors: Nann D, Nieser M, Sperveslage J, Henopp T, Vokuhl C,

Keywords: NET,