Table 1. Familial cancer risks conferred by affected parents and siblings.
| Cancer site | Patients with negative family history | 1 parent affected |
1 parent (age limited) affected1 |
1 sibling affected |
p-value for difference between RRsib and RRPar2 | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| N3 | RR4 | 95% CI5 | N | RR | 95% CI | N | RR | 95% CI | |||
| Upper aerodigestive tract | 7236 | 136 | 1.51 | (1.13–2.02) | 113 | 1.57 | (1.14–2.15) | 56 | 1.73 | (1.10–2.72) | 0.72 |
| Esophagus | 2248 | 26 | 2.45 | (1.55–3.90) | 18 | 2.33 | (1.34–4.05) | 12 | 3.36 | (1.70–6.62) | 0.41 |
| Stomach | 4411 | 222 | 1.72 | (1.47–2.02) | 172 | 1.78 | (1.49–2.13) | 46 | 2.97 | (2.11–4.18) | 0.0090 |
| Small intestine | 1489 | 17 | 4.81 | (2.99–7.75) | 14 | 5.34 | (3.16–9.01) | 14 | 10.11 | (5.98–17.09) | 0.09 |
| Colorectum | 25187 | 2945 | 1.72 | (1.64–1.80) | 2100 | 1.80 | (1.71–1.90) | 905 | 2.00 | (1.84–2.17) | 0.0294 |
| Liver | 4625 | 130 | 1.61 | (1.29–1.99) | 101 | 1.78 | (1.39–2.27) | 30 | 2.07 | (1.32–3.23) | 0.56 |
| Pancreas | 5152 | 178 | 1.96 | (1.66–2.33) | 140 | 2.09 | (1.73–2.54) | 54 | 2.73 | (2.01–3.71) | 0.15 |
| Lung | 18111 | 1346 | 1.86 | (1.74–1.99) | 1108 | 1.92 | (1.78–2.07) | 712 | 2.50 | (2.28–2.74) | <.0001 |
| Breast | 56566 | 6102 | 1.73 | (1.67–1.80) | 4989 | 1.78 | (1.70–1.85) | 3493 | 1.84 | (1.75–1.94) | 0.24 |
| Cervix | 8074 | 128 | 1.57 | (1.28–1.93) | 122 | 1.59 | (1.29–1.96) | 54 | 2.03 | (1.48–2.78) | 0.21 |
| Endometrium | 9298 | 301 | 2.21 | (1.88–2.61) | 257 | 2.37 | (1.98–2.83) | 128 | 2.13 | (1.66–2.73) | 0.49 |
| Ovary | 8633 | 261 | 2.52 | (2.20–2.88) | 241 | 2.67 | (2.32–3.07) | 122 | 2.97 | (2.44–3.61) | 0.38 |
| Prostate | 37805 | 6622 | 2.10 | (2.03–2.18) | 4469 | 2.33 | (2.24–2.43) | 3390 | 2.59 | (2.48–2.72) | 0.0005 |
| Testis | 6652 | 32 | 3.90 | (2.63–5.79) | 32 | 3.96 | (2.67–5.86) | 82 | 6.94 | (5.42–8.89) | 0.0173 |
| Kidney | 7739 | 201 | 1.58 | (1.34–1.87) | 175 | 1.68 | (1.40–2.01) | 75 | 2.09 | (1.59–2.75) | 0.18 |
| Urinary bladder | 10944 | 513 | 1.76 | (1.56–1.98) | 370 | 1.84 | (1.61–2.12) | 172 | 1.90 | (1.55–2.32) | 0.81 |
| Melanoma | 22807 | 763 | 2.43 | (2.23–2.66) | 643 | 2.55 | (2.32–2.81) | 584 | 2.74 | (2.48–3.03) | 0.31 |
| Skin, squamous cell | 8369 | 426 | 2.07 | (1.86–2.29) | 189 | 2.16 | (1.85–2.52) | 104 | 2.25 | (1.83–2.77) | 0.75 |
| Nervous system | 19099 | 371 | 1.54 | (1.35–1.75) | 349 | 1.58 | (1.38–1.80) | 215 | 1.71 | (1.44–2.03) | 0.45 |
| Thyroid gland | 4791 | 90 | 5.13 | (3.91–6.74) | 87 | 5.61 | (4.25–7.40) | 48 | 5.43 | (3.74–7.87) | 0.86 |
| Endocrine glands | 7810 | 130 | 2.05 | (1.61–2.62) | 110 | 1.99 | (1.53–2.59) | 60 | 1.98 | (1.38–2.83) | 0.98 |
| Non–Hodgkin lymphoma | 11895 | 276 | 1.61 | (1.41–1.84) | 203 | 1.65 | (1.41–1.93) | 124 | 1.69 | (1.38–2.06) | 0.85 |
| Hodgkin lymphoma | 3931 | 19 | 2.57 | (1.65–3.98) | 18 | 2.59 | (1.65–4.07) | 40 | 9.60 | (7.08–13.00) | <.0001 |
| Myeloma | 3296 | 61 | 2.12 | (1.64–2.74) | 40 | 1.96 | (1.43–2.68) | 22 | 2.73 | (1.79–4.18) | 0.21 |
| Leukemia | 12149 | 277 | 1.86 | (1.62–2.14) | 216 | 1.88 | (1.61–2.20) | 105 | 2.17 | (1.73–2.71) | 0.31 |
1Individuals were only considered to have a positive family history if the parental cancer was diagnosed at age ≤ 78 years.
2Risk estimates for limited parental age were considered for comparison.
3N = Number of cases with a concordant cancer in the family.
4RR = Relative risk.
5CI = Confidence interval.