The development of therapeutic resistance to targeted anticancer therapies remains a
significant clinical problem, with intratumoral heterogeneity playing a key role. In this context …

Recent advancements in breast cancer treatment have ushered in a new era of precision
medicine. Novel trials have led to the approval of a growing list of personalized therapies …

PURPOSE To update key recommendations of the American Society of Clinical
Oncology/College of American Pathologists estrogen (ER) and progesterone receptor (PgR) …

Purpose.—To update key recommendations of the American Society of Clinical
Oncology/College of American Pathologists estrogen receptor (ER) and progesterone …

Highlights•This ESO-ESMO ABC 5 Clinical Practice Guideline provides key
recommendations for managing advanced breast cancer patients.•It provides updates on …

Although 1% is the recommended cut-off to define estrogen receptor (ER) positivity, a 10%
cut-off is often used in clinical practice for therapeutic purposes. We here evaluate clinical …

Hormone receptor testing mainly serves the purpose of guiding treatment choices for breast
cancer patients. Patients with estrogen receptor (ER)‐positive breast cancers show …

Estrogen receptor (ER) status in breast cancer (BC) is determined using
immunohistochemistry (IHC) with nuclear expression in≥ 1% of cells defined as ER …

Introduction Traditionally, estrogen receptor (ER)-positive breast cancer has been defined
as tumors with≥ 1% positive for ER. The updated American Society of Clinical …

Endocrine responsiveness of primary breast cancers with borderline estrogen receptor
expression (ER+[1%-9%]) remains unclear. We aimed at investigating differences in …