1. What do the statistics on the HBOC indicate?
In breast cancer it is estimated that:
- About 12% of women in the general population will suffer from breast cancer sometime in their life.
- 55 to 65% of women who inherit harmful BRCA1 mutation will suffer from cancer at 70 years old.
- 45% of women who inherit a harmful BRCA2 mutation will suffer cancer at 70 years old.
In ovarian cancer it is estimated that:
- About 1.3% of women in the general population suffer from ovarian cancer sometime in their life.
- 39% of women who inherit harmful BRCA1 mutation suffer from cancer at 70 years old.
- 17% of women who inherit a mutated BRCA2 suffer harmful cancer at 70 years old.
2. Who is prone to HBOC?
There are different clinical criteria indicative of HBOC, which by its complexity, should be analyzed by a genetic counselor or specialist. To summarize, the most important criteria are listed below:
- An individual in a family with cases of deleterious mutation in BRCA1 / BRCA2.
- One case of breast cancer in a woman aged 45 or less.
- Diagnosis of breast and ovarian cancer in the same patient.
- Two cases of breast cancer in the same person, one of which is bilateral or a woman under 50 years of age.
- One case of breast cancer in women under age 50 bilateral, and one case of ovarian cancer of first or second grade.
- Three cases of breast and ovarian cancer (at least 1 case of ovarian) of first or second grade.
- Two cases of ovarian cancer of first or second grade.
- A case of male breast cancer and at least one first- or second-degree relative with breast and ovarian cancer.
- Having Ashkenazi Jewish descent.
Analyzing these it is important to consider the paternal side of the family because this is just as significant as the maternal side in determining the personal risk of developing breast cancer.
3. How to proceed if you suspect you have a family HBOC?
First, confirm if the family is at risk, for which the doctor makes a genetic history (family tree) where data on three generations (grandparents, parents, children) are obtained. In the genetic history data is collected on each individual of the family, if they lived or died, what illnesses they have or have had, age of onset of the disease, number of children, etc. These allow to estimate a figure of risk that is used by the genetic counselor to identify wha molecular study is suitable to be performed on each family member.
If the family is considered moderate or high risk, it is now possible to get genetic studies to identify which people in the family have inherited the mutated gene, BRCA1 and BRCA2 being the most currently studied. This allows you to take preventive measures in individuals carrying a mutation, while in those where the family mutation is not found, it will not be necessary to perform special preventive measures since, despite belonging to a family of high risk, if they have not inherited the mutated gene, their situation will be the same as the others. In general, the genes responsible for cancer, BRCA1 and BRCA2, pass on to 50% of the children of a person affected, which only half of the genetic testing would be required for a risk family.
We recommend that you contact your referring physician for a definite diagnosis, or you can consult our team of genetic counseling.