Risk of breast cancer in relatives who tested negative for mutation
| Group of relatives | Number | Number of observed cases | Number of expected cases | RR (95% CI) |
|---|---|---|---|---|
| FDR, first-degree relative. | ||||
| Relatives regardless of family history (analysis 1) | ||||
| All relatives | 257 | 28 | 5.3 | 5.3 (3.5 to 7.7) |
| FDRs only | 184 | 18 | 3.6 | 5.0 (2.9 to 7.8) |
| FDRs with no unexplained cases in family (analysis 2) | 4.0 (2.1 to 6.9) | |||
| Tested negative | 166 | 13 | 3.2 | |
| Untested affected | 63 | 7.7 (12% of 63) | 0.1 | |
| Untested unaffected | 188 | 0 | 3.1 | |
| Total | 20.7 | 6.4 | 3.2 (2.0 to 4.9) | |