Histological morphology of tumors with H&E staining
| Histologic Morphology | |
|---|---|
| Grade 1 (low) | Well differentiated: tumor mimics surrounding tissue morphology, gland formation, mucous production |
| Grade 2 (low) | Moderate differentiation: gland formation decreased (50%–75%), some recapitulation of normal features |
| Grade 3 (high) | Poorly differentiated: glands present but disorganized, decreased greatly; difficult to ascertain normal architecture |
| Grade 4 (high) | Undifferentiated: parent tissue morphology no longer recognizable |
Preliminary observation of the tumor using H&E staining may be useful in the designation of low- or high-grade tumor. Additional investigation, special stains, and immunohistochemistry are required for an in-depth examination of the tumor.