Based on the 'Claus plus method', the predicted risk of breast cancer of the 40-year-old woman in Figure 3 in the Antoniou paper was 31%.
The posterior probability of carrying a breast cancer predisposition gene in the individuals who developed breast cancer was assessed using the Cyrillic genetic risk package, based on the Claus model.
These risk categories represent the baseline objective CLTR of developing breast cancer, based on the tables of Claus (Claus et al, 1994).
The first was their cumulative lifetime risk (CLTR) for developing breast cancer, based on the tables of Claus (Claus et al, 1994) and additional information about the family history of ovarian cancer (Kriege et al, 2001).
Manual breast cancer risk assessment is largely based on the published Claus risk tables [ 30] and use of data in clearcut BRCA1/2 families from penetrance data for breast cancer [ 31].
For this reason, we extended the easy-to-use Claus tables into the 'Claus plus method' based on the Jonker model (Claus et al, 1994; Van Asperen et al, 2004).
The existing genetic models are either based on a single susceptibility gene (Claus et al, 1991) or take into account only the effects of BRCA1 and BRCA2 (Parmigiani et al, 1998) and hence they do not describe the familial breast cancer adequately.
These estimates are mostly calculated using the Claus tables and modified Claus method, and primarily based on a woman's age and family history, including the number of first-degree- or second-degree relatives with breast cancer and the ages of onset of breast cancer [ 41].
The most known model based on such a population is the Claus model, which predictions are in line with our results.
