Short-duration preoperative endocrine therapy alters molecular profiles to predict favourable outcome in ER+/HER2+ early breast cancer: a POETIC translational study.

ABSTRACT:

Background

About 15-20% of breast cancers (BC) overexpress Human Epidermal Growth Factor Receptor 2 (HER2+), and 50% of them are also oestrogen receptor positive (ER+). Patients with ER+/HER2+ BC with a limited response to systemic therapies are at an increased risk of relapse, thus understanding the mechanisms of resistance is crucial. This study investigates the changes in gene signature expression (ΔGSE) within ER+/HER2+ tumours and their intrinsic subtype (IS) in response to peri-operative aromatase inhibitors (POAI).

Methods

We analysed paired pre-treatment (baseline) and on-treatment (2wk) samples from 313 ER+/HER2+ BC from the POETIC trial using the BC360™ codeset. Early biological response to aromatase inhibitors (AI) was assessed by immunohistochemical Ki67 levels.

SUBMITTER: Sirven MB 

PROVIDER: S-EPMC12368290 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature