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

ER-low/HER2-negative tumours had a high rate of pCR after the KEYNOTE-522 regimen. Our results suggest that patients with ER-low HER2-negative BC should be treated as ER-null/HER2-negative BC in the neoadjuvant setting to maximise pCR.