Simple Summary Breast cancers (BCs) with a HER2 immunohistochemical score of 1+ or 2+
with negative in situ hybridization are referred as HER2-low BCs. The knowledge about the …

Background There is accumulating evidence support human epidermal growth factor
receptor 2 (HER2)-low as a biologically distinct subtype of breast cancer. The present study …

Background Metastatic breast cancers (MBC) with no expression of human epidermal
growth factor receptor-2 (HER2) are recently classified into two groups; HER2-zero [HER2 …

Abstract Cyclin‐dependent‐kinase‐4/6 inhibitor (CDK4/6i) plus endocrine therapy (ET) is
standard of care for patients with advanced hormone receptor (HR)‐positive, HER2 …

Background: The CDK4/6 inhibitor palbociclib combined with endocrine therapy (ET) has
proven to prolong progression-free survival (PFS) in women with hormone receptor-positive …

Data from 423 human epidermal growth factor receptor 2‐negative (HER2−), hormone
receptor‐positive (HR+) advanced breast cancer (aBC) patients treated with palbociclib and …

Background: Despite the approval of mTOR inhibitor everolimus and CDK4/6 inhibitors in
the management of hormone-receptor-positive HER2 non-amplified metastatic breast …

Introduction: Endocrine therapy and cyclin-dependent kinase (CDK) 4/6 inhibitors (CDK4/6i)
are standard treatment options for hormone receptor positive (HR+)/human epidermal …

Purpose Outcome data on hormone receptor positive (HR+), human epidermal growth factor
receptor 2 (HER2) nonamplified (HER2−) metastatic breast cancer (MBC) treated with …

Background Additional use of cyclin-dependent kinase 4/6 inhibitors with endocrine therapy
improves progression-free survival (PFS) in advanced hormone receptor (HR)-positive …