TABLE 2.
Histochemical and immunohistochemical characteristics of breast MECs.
| ID | CK7 | CK20 | CK5/6 | p40/p63 | EGFR | AREG | TILs | PD‐L1 | ALCIAN BLUE | MLH1 | MSH2 | MSH6 | PMS2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MUC_001 | + | − | + | + | 1+ | low (180) | 35% | 20 | 3 | R | R | H | H |
| MUC_002 | + | − | + | + | 3+ | low 20 | 0% | 0 | 1 | R | R | R | R |
| MUC_003 | + | − | + | − | 2+ | low (80) | 5% | 15 | 2 | R | R | R | L |
| MUC_004 | − | − | + | − | 2+ | high (240) | 20% | 0 | 1 | R | R | H | R |
| MUC_005 | + | − | + | + | 1+ | low (120) | 0% | 10 | 3 | H | R | H | H |
| MUC_006 | n/a | n/a | n/a | n/a | 3+ | low (40) | 80% | n/a | 1 | n/a | n/a | n/a | n/a |
| MUC_007 | n/a | n/a | n/a | + | 2+ | n/a | 2% | n/a | 2 | n/a | n/a | n/a | n/a |
| MUC_008 | n/a | n/a | + | + | 3+ | n/a | 5% | n/a | 1 | n/a | n/a | n/a | n/a |
| MUC_009 | n/a | n/a | n/a | n/a | n/a | n/a | n/a | n/a | n/a | n/a | n/a | n/a | n/a |
| MUC_010 | + | − | − | − | 2+ | high (300) | 80% | 20 | 2 | R | R | R | R |
| MUC_011 | n/a | n/a | n/a | n/a | n/a | n/a | 10% | n/a | 1 | n/a | n/a | n/a | n/a |
| MUC_012 | n/a | n/a | n/a | n/a | n/a | n/a | 2% | n/a | 3 | n/a | n/a | n/a | n/a |
| MUC_013 | n/a | n/a | n/a | + | n/a | n/a | 0% | n/a | 2 | n/a | n/a | n/a | n/a |
Abbreviations: AREG, amphiregulin; CK, cytokeratin; H, heterogeneous; L, low; MLH1, mutL homolog 1; MSH2, mutS homolog 2; MSH6, mutS homolog 6; PD‐L1, programmed death ligand 1; PMS2, postmeiotic segregation increased 2; R, retained; TILs, Tumor‐infiltrating lymphocytes.