| Term | Definition |
| Visible dysplasia | Dysplasia identified on targeted biopsies from a lesion visualized at colonoscopy |
| Polypoid | Lesion protruding from the mucosa into the lumen ≥2.5 mm |
| | Lesion attached to the mucosa by a stalk |
| | Lesion not attached to the mucosa by a stalk (entire base is contiguous with the mucosa) |
| Nonpolypoid | Lesion with little (<2.5 mm) or no protrusion above the mucosa |
| | Lesion with protrusion but <2.5 mm above the lumen (less than the height of the closed cup of a biopsy forceps) |
| | Lesion without protrusion above the mucosa |
| | Lesion with at least a portion depressed below the level of the mucosa |
| General descriptors |
| | Ulceration (fibrinous-appearing base with depth) within the lesion |
| |
| | Lesion's border is discrete and can be distinguished from surrounding mucosa |
| | Lesion's border is not discrete and cannot be distinguished from surrounding mucosa |
| Invisible dysplasia | Dysplasia identified on random (non-targeted) biopsies of colon mucosa without a visible lesion |
