HER2-low status as a distinct breast cancer subtype: myth or truth? Analysis of the WSG trials WSG-ADAPT-HR+/HER2-, WSG-PlanB, and WSG-ADAPT-TN.

ABSTRACT:

Background

New data show that not only HER2-overexpressing breast cancer (BC) tumors but also HER2-low tumors, classically considered as HER2-negative, respond to HER2-targeting antibody-drug-conjugates. Our objective was to analyze the prevalence of HER2-low BC in a pooled analysis of contemporary early BC trials and to evaluate its role as a prognostic factor in terms of survival in comparison to HER2-zero BC.

Methods

We evaluated 5598 patients with locally HR + /HER2- BC from the screening cohort of WSG-ADAPT-HR + /HER2-, 2592 patients with HR + /HER2- or HR-/HER2- from the adjuvant WSG-PlanB trial, and 336 patients from the WSG-ADAPT-TN trial. Central HER2 testing was performed prospectively in WSG-ADAPT and retrospectively in WSG-PlanB. Following ASCO/CAP guidelines, HE

SUBMITTER: Schmidt G 

PROVIDER: S-EPMC11827153 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature