Table 2.
Immunohistochemical and biomolecular features.
| Methods | Markers | Expression | References |
|---|---|---|---|
| IHC | CK7 CAM5.2 AE1/3 EMA |
Only in some cases in a focal/weak manner | [58] |
| P40 P63 TTF1 Desmin NUT S100 WT-1 |
Usually negative | [58,60] | |
| Vimentin Synaptophysin |
Positive in some cases | [38] | |
| SOX2 SALL4 CD34 |
Positive | [60] | |
| Claudin-4 | Negative | [60] | |
| CD138 CD99 CD30 |
Focal and weak expression | [61] | |
| SMARCA2 | Negative (different from SMARCA4-deficient NSCLC) | [58,61] | |
| SMARCAB-1 | Overexpression | ||
| NGS | P53 | 81–56% | [64,65] |
| KEAP1 | 41% | ||
| STK11 | 39–15% | ||
| Kras | 36–15% | ||
| NF1 | 15% | ||
| PTEN | 11% | ||
| EGFR | Negative | [66] | |
| NGS/IHC/FISH | ROS1 | Negative | |
| ALK | Some cases reported in the literature | [4,66] |