Squamous Carcinoma of the Esophagus
Supplemental Studies
Immunohistology
- Basaloid squamous carcinoma
| p63 |
Positive, usually extensive |
| Keratin, including high molecular weight |
Positive, varying reports on extent of staining |
| S100 |
25% focal positive |
| Actin, including smooth muscle |
Negative (one report of 15% focal weak staining) |
| p16 |
Usually negative |
- Spindle cell squamous carcinoma (spindle cell component)
| p63 |
Positive, probably about 50% |
| High molecular weight cytokeratin |
Positive, probably about 50% |
| Low molecular weight cytokeratin |
Positive but less sensitive than HMWCK |
| Smooth muscle actin |
May be positive in spindled tumors NOS, usually focally, (based on similar tumors of ENT sites) |
| Actins, desmin, other muscle markers |
Depending upon presence and type of differentiation, may be strongly and extensively positive (rare cases) |
