Table 2. Relative risk of colorectal cancer according to history of cholecystectomy among 85 184 women of the NHSa.
|
Cholecystectomy |
||
|---|---|---|
| Subsite | Number | RR (95% CI) |
| Proximal colon cancerb | ||
| ARR | 46 | 1.34 (0.97–1.84) |
| MRR | 1.35 (0.97–1.88) | |
| Distal colon cancerb | ||
| ARR | 28 | 0.93 (0.63–1.38) |
| MRR | 0.95 (0.64–1.43) | |
| All colon cancer | ||
| ARR | 74 | 1.15 (0.90–1.47) |
| MRR | 1.17 (0.91–1.51) | |
| Rectal cancer | ||
| ARR | 32 | 1.69 (1.14–2.50) |
| MRR | 1.58 (1.05–2.36) | |
| Total colorectal cancer | ||
| ARR | 133 | 1.21 (1.01–1.46) |
| MRR | 1.19 (0.98–1.44) | |
a
ARR, age-adjusted relative risk; MRR, multivariate relative risk; RR, relative risk; CI, confidence interval.
b
Proximal colon denotes the segment from the cecum to the splenic flexure, and distal colon denotes the segment from the splenic flexure to the rectosigmoid junction. The numbers of colon and rectal cancers may not be equal to the total number of colorectal cancers because in some cases the specific site of the cancer was unknown.