A predictive endocrine resistance index accurately stratifies luminal breast cancer treatment responders and nonresponders.

ABSTRACT: BACKGROUNDEndocrine therapy (ET) with tamoxifen (TAM) or aromatase inhibitors (AI) is highly effective against hormone receptor-positive (HR-positive) early breast cancer (BC), but resistance remains a major challenge. The primary objectives of our study were to understand the underlying mechanisms of primary resistance and to identify potential biomarkers.METHODSWe selected more than 800 patients in 3 subcohorts (Discovery, n = 364, matched pairs; Validation 1, n = 270, Validation 2, n = 176) of the West German Study Group (WSG) ADAPT trial who underwent short-term preoperative TAM or AI treatment. Treatment response was assessed by immunohistochemical labeling of proliferating cells with Ki67 before and after ET. We performed comprehensive molecular profiling, including targeted next-gen

SUBMITTER: Zhang G 

PROVIDER: S-EPMC12483570 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature