Clinical characteristics of colorectal cancer according to tumour location bowel subsite
| Clinical feature | Total N | Caecum | Ascending colon | Hepatic flexure | Transverse colon | Splenic flexure | Descending colon | Sigmoid colon | Rectosigmoid | Rectum | p Value |
| All cases | 1443 | 243 | 295 | 46 | 91 | 33 | 83 | 314 | 106 | 232 | |
| Sex | <0.0001 | ||||||||||
| Male (HPFS) | 649 (45%) | 129 (53%) | 95 (32%) | 28 (61%) | 34 (37%) | 18 (55%) | 34 (41%) | 149 (47%) | 51 (48%) | 111 (48%) | |
| Female (NHS) | 794 (55%) | 114 (47%) | 200 (68%) | 18 (39%) | 57 (63%) | 15 (46%) | 49 (59%) | 165 (53%) | 55 (52%) | 121 (52%) | |
| Mean age ±SD | 68.4±8.9 | 69.2±8.6 | 70.9±8.4 | 71.3±8.8 | 67.0±8.4 | 67.2±9.6 | 65.8±8.8 | 67.4±8.3 | 67.4±9.1 | 67.4±9.6 | <0.0001 |
| Body mass index | 0.35 | ||||||||||
| <30 kg/m2 | 1161 (81%) | 209 (86%) | 241 (83%) | 35 (76%) | 72 (79%) | 24 (75%) | 65 (78%) | 246 (79%) | 83 (81%) | 186 (81%) | |
| ≥30 kg/m2 | 269 (19%) | 33 (14%) | 48 (17%) | 11 (24%) | 19 (21%) | 8 (25%) | 18 (22%) | 67 (21%) | 20 (19%) | 45 (19%) | |
| Year of diagnosis | 0.0024 | ||||||||||
| Before 1995 | 459 (32%) | 65 (27%) | 75 (25%) | 10 (22%) | 32 (35%) | 13 (39%) | 29 (35%) | 124 (39%) | 28 (26%) | 83 (36%) | |
| 1995–2006 | 984 (68%) | 178 (73%) | 220 (75%) | 36 (78%) | 59 (65%) | 20 (61%) | 54 (65%) | 190 (61%) | 78 (74%) | 149 (64%) | |
| Family history of colorectal cancer in any first-degree relative | 0.15 | ||||||||||
| Absent | 1162 (81%) | 190 (79%) | 225 (78%) | 38 (83%) | 73 (80%) | 23 (72%) | 69 (83%) | 254 (81%) | 90 (87%) | 200 (87%) | |
| Present | 270 (19%) | 52 (21%) | 65 (22%) | 8 (17%) | 18 (20%) | 9 (28%) | 14 (17%) | 59 (19%) | 14 (13%) | 31 (13%) | |
| Prediagnosis physical activity (MET-hours/week) | 0.058 | ||||||||||
| <18 | 803 (59%) | 129 (55%) | 184 (65%) | 20 (43%) | 44 (53%) | 18 (60%) | 50 (63%) | 182 (63%) | 56 (55%) | 120 (57%) | |
| ≥18 | 550 (41%) | 104 (45%) | 97 (35%) | 26 (57%) | 39 (47%) | 12 (40%) | 29 (37%) | 108 (37%) | 45 (45%) | 90 (43%) | |
| Prediagnosis smoking status | 0.16 | ||||||||||
| Never | 571 (41%) | 108 (45%) | 108 (38%) | 19 (41%) | 36 (40%) | 12 (38%) | 24 (29%) | 141 (45%) | 38 (38%) | 85 (38%) | |
| Former/current smokers | 839 (60%) | 131 (55%) | 178 (62%) | 27 (59%) | 54 (60%) | 20 (63%) | 59 (71%) | 169 (55%) | 62 (62%) | 139 (62%) | |
| Prediagnosis alcohol consumption | 0.50 | ||||||||||
| No | 468 (33%) | 84 (35%) | 104 (36%) | 12 (26%) | 31 (34%) | 14 (44%) | 18 (22%) | 98 (31%) | 32 (31%) | 75 (33%) | |
| <15 g/day | 661 (46%) | 113 (47%) | 132 (46%) | 21 (46%) | 44 (48%) | 11 (34%) | 45 (54%) | 146 (47%) | 52 (50%) | 95 (43%) | |
| ≥15 g/day | 298 (21%) | 45 (19%) | 52 (18%) | 13 (28%) | 16 (18%) | 7 (22%) | 20 (24%) | 69 (22%) | 20 (19%) | 56 (25%) |
(%) Indicates the proportion of cases with a specific clinical feature among cancers located in each subsite (caecum, ascending colon, hepatic flexure, transverse colon, splenic flexure, descending colon, sigmoid colon, rectosigmoid or rectum). p Values were calculated by the χ2 test, except for age (one-way analysis of variance test).
HPFS, Health Professionals Follow-up Study; MET, metabolic equivalent task; NHS, Nurses' Health Study.