| Polyposis registry | Total number of CRCs | Number of CRCs (%) diagnosed | ||
| 0–10 years | 11–15 years | 16–20 years | ||
| The Netherlands | 106 | 0 | 1 | 1 |
| Denmark | 190 | 0 | 0 | 3 |
| Germany | 524 | 0 | 1 | 7 |
| St Mark’s | 96 | 0 | 0 | 3 |
| Finland | 157 | 0 | 0 | 1 |
| Total | 1073 | 0 | 2 (0.2%) | 15 (1.3%) |
*Communicated with registries.
CRC, colorectal cancer, FAP, familial adenomatous polyposis.