Loss of O6-Methylguanine-DNA Methyltransferase Protein Expression by Immunohistochemistry Is Associated With Response to Capecitabine and Temozolomide in Neuroendocrine Neoplasms.

ABSTRACT:

Background

A recent prospective phase II study (ECOG-ACRIN E2211) demonstrated that MGMT deficiency was associated with a significant response to capecitabine and temozolomide (CAPTEM) in pancreatic neuroendocrine neoplasms (NENs); however, routine MGMT analysis in NENs was not recommended. Our study sought to demonstrate whether loss of MGMT protein expression is associated with improved overall survival (OS) in patients receiving CAPTEM for NENs from various tumor sites.

Materials and methods

Paraffin-embedded tumor samples were evaluated by immunohistochemistry (IHC) using an MGMT monoclonal antibody. Intact MGMT protein expression (i.e., IHC positivity) was defined as any staining intensity (> 1+) in ≥ 36% of neoplastic cells according to an internal validation study. IH

SUBMITTER: Evans MG 

PROVIDER: S-EPMC11994148 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature