Table 3.
Location of new CRC according to age group
| Age (years) | Total | Right | Left | Rectum | Right/left | Right/rectum |
|---|---|---|---|---|---|---|
| <40 | 8,087 | 2,688 | 2,680 | 2,719 | 1.00* | 0.99* |
| 40–49 | 19,787 | 6,313 | 6,624 | 6,850 | 0.95* | 0.92* |
| 50–59 | 50,231 | 18,151 | 16,706 | 15,374 | 1.09* | 1.18* |
| 60–69 | 64,942 | 29,346 | 19,419 | 16,177 | 1.51* | 1.81* |
| ≥70 | 127,343 | 75,193 | 31,339 | 20,811 | 2.40* | 3.61* |
| Total | 270,390 | 131,691 | 76,768 | 61,931 | 1.72* | 2.13* |
Notes:
*
The proportion of right-sided lesions increased with age (P=0.01, by chi-squared trend test). Left column reflects left-sided colon cancer; right column reflects right-sided colon cancer. The Right/left column reflects the means the ratio of right-sided colon cancer to left-sided and the Right/rectum column reflects the ratio of right-sided colon cancer to rectum cancer.
Abbreviation: CRC, colorectal cancer.