Prevalence and number of polyps removed prior to or during clearing, during surveillance prior to inclusion and during protocolised surveillance
| During/prior to clearing (n=271) | Surveillance prior to study inclusion (n=84) | Surveillance after study inclusion using personalised surveillance protocol | |||||
| Surveillance 1 (n=271) | Surveillance 2 (n=173) | Surveillance 3 (n=66) | Surveillance 4 (n=15) | Surveillance 5 (n=1)* | |||
| Patients with CRC, n (%) | 69 (25%) | 0 | 0 | 1 | 1 | 0 | 0 |
| Patients with ≥1 polyp | 271 (100%) | 81 | 214 (79%) | 132 (76%) | 56 (85%) | 15 (100%) | 1 |
| Number of polyps per patient, median (range) | 22 (1–157) | 8 (0–39) | 3 (0–19) | 2 (0–20) | 2 (0–13) | 3 (1–9) | 2 |
| Patients with ≥1 advanced polyp† | 237 (87%) | 25 (30%) | 73 (27%) | 31 (18%) | 12 (8%) | 6 (40%) | 0 |
| Patients with at least one: | |||||||
| Any SP | 271 (100%) | 78 (93%) | 195 (72%) | 121 (70%) | 45 (68%) | 13 (87%) | 1 |
| HP | 249 (92%) | 77 (92%) | 148 (55%) | 83 (48%) | 25 (38%) | 11 (73%) | 0 |
| SSL | 215 (79%) | 37 (44%) | 106 (39%) | 64 (37%) | 27 (41%) | 4 (27%) | 0 |
| TSA | 15 (5.9%) | 4 (5%) | 1 (0.4%) | 2 (1.2%) | 1 (1.5%) | 0 | 0 |
| SP ≥10 mm | 192 (71%) | 13 (16%) | 58 (21%) | 28 (16%) | 7 (11%) | 4 (27%) | 0 |
| SP with dysplasia | 61 (23%) | 7 (8%) | 7 (3%) | 5 (2.9%) | 5 (8%) | 0 | 0 |
| Median number of SP per patient (range): | |||||||
| Any SP | 17 (1–116) | 6 (0–31) | 2 (0–17) | 2 (0–20) | 1.5 (0–13) | 2 (0–8) | 2 |
| HP | 9 (0–114) | 4 (0–31) | 1 (0–13) | 0 (0–10) | 0 (0–8) | 1 (0–7) | 0 |
| SSL | 4 (0–55) | 0 (0–23) | 0 (0–15) | 0 (0–11) | 0 (0–13) | 0 (0–3) | 0 |
| TSA | 0 (0–7) | 0 (0–5) | 0 (0–6) | 0 (0–1) | 0 (0–1) | 0 (0–0) | 0 |
| SP ≥10 mm | 2 (0–25) | 0 (0–5) | 0 (0–7) | 0 (0–4) | 0 (0–3) | 0 (0–2) | 0 |
| SP with dysplasia | 0 (0–14) | 0 (0–5) | 0 (0–6) | 0 (0–2) | 0 (0–3) | 0 (0–0) | 0 |
| Patients with at least one adenoma: | 216 (80%) | 58 (69%) | 113 (42%) | 60 (35%) | 21 (32%) | 7 (47%) | 0 |
| Advanced adenoma ‡ | 131 (48%) | 8 (9%) | 20 (7.4%) | 3 (2.3%) | 1 (1.5%) | 2 (13%) | 0 |
| Median number of adenomas per patient | 3 (0–41) | 1.5 (0–16) | 0 (0–10) | 0 (0–8) | 0 (0–8) | 0 (0–4) | 0 |
| Advanced adenoma | 0 (0–7) | 0 (0–1) | 0 (0–2) | 0 (0–2) | 0 (0–1) | 0 (0–1) | 0 |
*This column represents only one patient. Therefore, no median or range is given.
↵†Advanced polyp: advanced adenoma (≥25% villous histology, high-grade dysplasia and ≥10 mm in diameter)/advance.
↵‡Advanced adenoma: ≥25% villous histology, high-grade dysplasia and ≥10 mm in diameter.
CRC, colorectal cancer; HP, hyperplastic polyp; FDR, first-degree relative; FOBT, faecal occult blood test; SP, serrated polyp; SPS, serrated polyposis syndrome; SSL, sessile serrated lesion; TSA, traditional serrated adenoma.