Table 3.
Comparison of the estimated number of radiation-related cancer deaths with the number of colorectal cancer deaths prevented by CT colonography screening every five years (per 100,000): according to microsimulation model and age at screening
| Microsimulation model | Age at screening | Average no. of screens (per person) | Colorectal cancer deaths prevented | Radiation-induced cancer deaths | Benefit-risk ratio (prevented:induced) | ||
|---|---|---|---|---|---|---|---|
| (per 100,000) | (per 100,000) | (95% UL) | (95% UL) | ||||
| MISCAN | 50-80 yrs | 3.5 | 2080 | 60 | (30-110) | 35:1 | (19:1-69:1) |
| 40-80 yrs | 4.5 | 2150 | 90 | (40-150) | 24:1 | (14:1-54:1) | |
| 65-80 yrs | 2.0 | 1620 | 20 | (10-50) | 81:1 | (32:1-162:1) | |
| 50-64 yrs* | 2.3 | 460 | 40 | (30-80) | 11:1 | (6:1-15:1) | |
| 40-49 yrs** | 1.8 | 70 | 40 | (20-80) | 2:1 | (0.9:1-4:1) | |
| CRC-SPIN | 50-80 yrs | 3.5 | 2370 | 60 | (30-110) | 40:1 | (22:1-79:1) |
| 40-80 yrs | 4.5 | 2500 | 90 | (40-150) | 28:1 | (17:1-63:1) | |
| 65-80 yrs | 2.0 | 1740 | 20 | (10-50) | 87:1 | (35:1-174:1) | |
| 50-64 yrs* | 2.3 | 630 | 40 | (30-80) | 16:1 | (8:1-21:1) | |
| 40-49 yrs** | 1.8 | 130 | 40 | (20-80) | 3:1 | (2:1-7:1) | |
| SimCRC | 50-80 yrs | 3.5 | 2790 | 60 | (30-110) | 47:1 | (25:1-93:1) |
| 40-80 yrs | 4.5 | 3030 | 90 | (40-150) | 34:1 | (20:1-76:1) | |
| 65-80 yrs | 2.0 | 1820 | 20 | (10-50) | 91:1 | (36:1-182:1) | |
| 50-64 yrs* | 2.3 | 970 | 40 | (30-80) | 24:1 | (12:1-32:1) | |
| 40-49 yrs** | 1.8 | 240 | 40 | (20-80) | 6:1 | (3:1-12:1) | |
*
Additional benefit/risk from CT colonography screening age 50-64, assuming screening continues age 65-80.
**
Additional benefit/risk from CT colonography screening age 40-49, assuming screening continues age 50-80.
Radiation risks from screening 40-49, 50-64 and 65-80 do not equal the sum of the risks from screening 40-80 or 50-80 because the total number of CT colonography screens performed is different. UL – uncertainty limits.