PD-L1 status in tumour cells of MBCs and invasive ductal carcinoma cases (46% in metaplastic vs 6%–9% in other subtypes combined, p<0.001)
| Breast cancer subtype | PD-L1 status Cut-off ≥2+ intensity/≥5% tumour cells | Total | |
|---|---|---|---|
| Negative | Positive | ||
| Metaplastic carcinoma | 39 (54%) | 33 (46%) | 72 |
| TNBC-NOS | 93 (91%) | 9 (9%) | 102 |
| HER2-positive breast cancer | 30 (94%) | 2 (6%) | 32 |
| Hormone-positive breast carcinoma | 79 (94%) | 5 (6%) | 84 |
| Total | 241 (83%) | 49 (17%) | 290 |
HER2, human epidermal growth factor receptor 2; MBC, metaplastic breast carcinoma; PD-L1; programmed death-ligand 1; TNBC, triple-negative breast cancer.