Skip to main content

Table 2 The effect of the various patterns of breast cancer in the family on the age of onset of breast cancer in the women under study (univariate) *

From: A family history of breast cancer will not predict female early onset breast cancer in a population-based setting

Family characteristics

Relative risk at

age 30**

95% C.I.

relative risk at

of age 30

Change of

relative risk per

10 years ***

Overall

Significance

****

≥ 2 cases of female breast cancer in first or second-degree relatives (yes vs. no)

2.20

1.15–4.22

0.851

P = .013

≥ 2 cases of female breast cancer in first-degree relatives (yes vs. no)

4.28

1.89–9.70

0.624

P = .001

≥ 1 case of female breast cancer under age 50 (yes vs. no)

2.82

1.43–5.57

0.800

P = .001

≥ 2 cases of female breast cancer under age 50 (yes vs. no)

5.81

2.16–15.60

0.825

P = .002

≥ 1 case of female breast cancer under age 40 (yes vs. no)

3.21

1.36–7.56

0.825

P = .001

Bilateral breast cancer in affected sister (index patient) (yes vs. no)

4.00

1.55–10.32

0.784

P = .000

Ovarian cancer (yes vs. no)

2.72

0.58–12.83

0.801

P = .294

DCIS in affected sister (index patient) (yes vs. no)

0.89

0.30–2.63

1.184

P = .412

  1. * Due to small numbers, results regarding ≥ 2 cases under age 40 and ≥ 1 or 2 case under age 30 of female breast cancer, male breast cancer, breast and ovarian cancer in one person and prostate cancer under age 60 are not presented.
  2. ** Due to low prevalence, the hazard ratio can be considered as a relative risk.
  3. *** The relative risk at age 30 can be multiplied with this factor for calculating the relative risk at age 40, age 50 and so on.
  4. **** Model significance was based on the likelihood ratio of the final model as compared to the O-model without any covariate.