Biomarkers Significance 6/10

DAXX/ATRX and ALT Testing Refines Pancreatic Neuroendocrine Tumor Classification (Reprint)

This corrected reprint reaffirms the prognostic value of DAXX/ATRX protein loss by immunohistochemistry and alternative lengthening of telomeres by FISH in pancreatic neuroendocrine tumors. These biomarkers help stratify patients beyond conventional grading, distinguish PanNETs from neuroendocrine carcinomas, and identify pancreatic origin in metastases of unknown primary. The practical guidance on testing nuances makes this a useful reference for pathology laboratories.

The original study

Reprint of: The Diagnostic and Prognostic Utility of Incorporating DAXX, ATRX, and Alternative Lengthening of Telomeres (ALT) to the Evaluation of Pancreatic Neuroendocrine Tumors (PanNETs).

Authors
Heaphy CM, Singhi AD
Journal
Human pathology
Type
Journal Article, Review, Corrected and Republished Article
PMID
36702689
Read the original study →

Original abstract

Pancreatic neuroendocrine tumors (PanNETs) are a heterogeneous group of neoplasms with increasing incidence and an ill-defined pathobiology. Although many PanNETs are indolent and remain stable for years, a subset may behave aggressively and metastasize widely. Thus, the increasing and frequent detection of PanNETs presents a treatment dilemma. Current prognostic systems are susceptible to interpretation errors, sampling issues, and do not accurately reflect the clinical behavior of these neoplasms. Hence, additional biomarkers are needed to improve the prognostic stratification of patients diagnosed with a PanNET. Recent studies have identified alterations in death domain-associated protein 6 (DAXX) and alpha-thalassemia/mental retardation X-linked (ATRX), as well as alternative lengthening of telomeres (ALT), as promising prognostic biomarkers. This review summarizes the identification, clinical utility, and specific nuances in testing for DAXX/ATRX by immunohistochemistry and ALT by telomere-specific fluorescence in situ hybridization in PanNETs. Furthermore, a discussion on diagnostic indications for DAXX, ATRX, and ALT status is provided to include the distinction between PanNETs and pancreatic neuroendocrine carcinomas (PanNECs), and determining pancreatic origin for metastatic neuroendocrine tumors in the setting of an unknown primary.