Modified Spigelman and Kashiwagi classifications
| Modified Spigelman classification for duodenal assessment | |||
| Score | |||
| Criterion | 1 point | 2 points | 3 points |
| Number of polyps | 1–4 | 5–20 | >20 |
| Polyp size (mm) | 1–4 | 5–10 | >10 |
| Histological architecture | Tubular | Tubulovillous | Villous |
| Dysplasia | Low grade | – | High grade |
| Stage | |||||
| Number of points | 0 | 1–4 | 5–6 | 7–8 | 9–12 |
| Stage | 0 | I | II | III | IV |
| Kashiwagi classification for ampullary assessment | ||
| Criterion | Minor ampullary polyposis | Major ampullary polyposis |
| Size | <10 mm | ≥10 mm |
| Histological architecture | Tubular | Tubulovillous or villous |
| Dysplasia | Low | High |
Adapted from Saurin et al and Kashiwagi et al.11 17