Cancer Risks for Relatives of Children with Cancer

Table 2

Number of observed (O) and expected cancers (E) and standardised incidence ratios (SIR) and 95% confidence interval (95% CI) for cancer risk for relatives of proband.

Relationship to proband	O	E	SIR	95% CI
First-degree	28	19.8	1.45	0.98–2.21
Male	10	10.3	0.97	0.51–1.99
Female	18	8.9	2.00	1.26–3.39
Parents	25	18.7	1.36	0.93–2.08
Fathers	8	9.7	0.82	0.40–1.86
Mothers	17	8.4	2.00	1.27–3.33
Siblings	3	1.0	2.93	0.93–14.1
Second-degree	325	375.9	0.86	0.77–0.97
Male	163	208.4	0.78	0.67–0.91
Female	162	167.6	0.97	0.84–1.12
Grandparents	258	318.0	0.81	0.72–0.92
Grandfathers	144	183.2	0.79	0.67–0.92
Grandmothers	114	134.9	0.85	0.71–1.01
Uncles and Aunts	67	57.9	1.16	0.90–1.52
Uncles	19	25.2	0.75	0.46–1.32
Aunts	48	32.7	1.47	1.11–1.99