Table 4.
Characteristic of CRC cases according to participants’ first endoscopic findings in the three cohorts (NHS [1990-2012], NHS2 [1989-2013] and HPFS [1990-2012]) a
| Non-polyp |
Overall polyps |
High-risk polyps |
|||
|---|---|---|---|---|---|
| (n=427) | Conventional adenomas (n=51) | Serrated polyps (n=24) | Advanced conventional adenomas (n=39) | Large serrated polyps (≥10 mm) (n=5) | |
| Age at diagnosis, year | 72 (65-78) | 74 (62-80) | 73 (61-78) | 73 (62-79) | 59 (52-77) |
| P | 0.69 | 0.79 | 0.99 | 0.09 | |
| Interval between the first endoscopy and diagnosis of CRC, year | 6 (3-10) | 6 (4-8) | 6 (4-8) | 6 (4-8) | 6 (3-6) |
| P | 0.95 | 0.26 | 0.55 | 0.30 | |
| Family history of CRC, n (%) | |||||
| No | 309 (72) | 43 (84) | 20 (83) | 32 (82) | 4 (80) |
| Yes | 118 (28) | 8 (16) | 4 (17) | 7 (18) | 1 (20) |
| P | 0.09 | 0.34 | 0.26 | 1.00 | |
| Pack-years of smoking | 2.0 (0-23.0) | 7.0 (0-28.0) | 10.5 (0.5-25.5) | 8.5 (0-33.0) | 8.0 (0-17.0) |
| P | 0.59 | 0.34 | 0.32 | 0.65 | |
| Body mass index, kg/m2 | 25.8 (23.1-28.8) | 26.1 (23.4-28.3) | 25.0 (23.1-27.7) | 26.1 (23.4-28.1) | 30.4 (22.7-45.8) |
| P | 0.67 | 0.89 | 0.81 | 0.29 | |
| Alcohol intake, g/day | 1.5 (0-6.9) | 7.8 (0.4-18.2) | 3.4 (0-15.0) | 8.4 (2.2-18.2) | 3.7 (1.1-6.0) |
| P | 0.009 | 0.16 | 0.007 | 0.81 | |
| Colorectal cancer subsite, n (%) | |||||
| Proximal colon | 238 (56) | 28 (55) | 16 (67) | 19 (49) | 3 (60) |
| Distal colon | 77 (18) | 11 (22) | 3 (13) | 10 (26) | 0 |
| Rectum | 67 (16) | 4 (8) | 3 (13) | 3 (8) | 2 (40) |
| Unidentified or multi-region | 45 (11) | 8 (16) | 2 (8) | 7 (18) | 0 |
| P | 0.35 | 0.74 | 0.26 | ||
| Colorectal cancer stage, n (%) | |||||
| Stage I | 96 (22) | 9 (18) | 5 (21) | 7 (18) | 1 (20) |
| Stage II | 94 (22) | 13 (25) | 5 (21) | 10 (26) | 1 (20) |
| Stage III or IV | 148 (35) | 13 (25) | 8 (33) | 9 (23) | 2 (40) |
| Unknown | 89 (21) | 16 (31) | 6 (25) | 13 (33) | 1 (20) |
| P | 0.26 | 0.97 | 0.22 | 1.00 | |
Abbreviations: CRC, colorectal cancer; SP, serrated polyp; NHS, the Nurses’ Health Study; HPFS, the Health Professionals Follow-up Study; OR, odd ratio; CI, confidence interval.
a
Median (interquartiles) is presented for continuous variables and number of participants (percentage) for categorical variables. Advanced conventional adenomas were defined as at least one conventional adenoma of ≥10 mm in diameter or with advanced histology (tubulovillous/villous histological features or high grade or severe dysplasia), otherwise were defined as non-advanced conventional adenomas.