Clinical characteristics of ulcerative colitis patients, n=517
| UC no CRC (n=505) | CRC after UC diagnosis (n=8) | CRC prior to UC diagnosis (n=4) | Total (n=517) | |
| Male | 255 | 5 | 4 | 264 (51%) |
| Age at UC diagnosis (years) | 37 (4 to 88) | 40 (25 to 62) | 79 (74 to 82) | |
| Age at CRC diagnosis (years) | 56 (39 to 88) | 69 (64 to 79) | ||
| Time from UC diagnosis to CRC (years) | 22 (1 to 23) | −6.5 (−18 to −2) | ||
| CRC location | missing n=2 | |||
| Rectum | 3 | 1 | ||
| Left colon (excluding rectum) | 1 | 1 | ||
| Right colon | 4 | |||
| Maximum extent of UC at any time | ||||
| Proctitis | 168 | 1 | 169 (33%) | |
| Left sided | 174 | 1 | 3 | 178 (34%) |
| Extensive | 163 | 6 | 1 | 170 (33%) |
| Primary sclerosing cholangitis | 14 | 1 | 0 | 15 (3%) |
| First-degree relative with CRC (missing n=70) | 37 | 1 | 0 | 38 (7.6%) |
CRC, colorectal cancer; UC, ulcerative colitis.