PROMENADE: pembrolizumab for early ER-low/HER2-negative breast cancer, real-world French cohort.

ABSTRACT:

Background

In the phase III KEYNOTE-522 study (NCT03036488), which defined triple-negative breast cancers (TNBCs) as tumours with an estrogen receptor (ER) level ≤1% (ER-null) according to European Society for Medical Oncology (ESMO) and American Society of Clinical Oncology (ASCO) guidelines, the rate of pathological complete response (pCR) was increased by pembrolizumab addition to neoadjuvant chemotherapy. This combination has become the standard of care for stage II or III TNBC. However, updated ASCO guidelines suggest that tumours with low ER levels should be treated as ER-null. In some European countries, tumours with 1%-9% ER expression, called 'ER-low', are considered and treated as ER-null despite a lack of data concerning this population.

Patients and methods

We co

SUBMITTER: Cherifi F 

PROVIDER: S-EPMC12689199 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature