“My mother had cancer ten years ago, she died at the age of 56”: in May 2013, Angelina Jolie revealed that she had decided to voluntarily have both breasts removed in order to prevent the onset of breast cancer, cancer that took her mother’s life.
However, this exceptional situation concerns only a few women: 5% of breast cancers are the result of a hereditary mutation of a gene out of the 53,000 totaled each year in France (1).
The genetic predisposition induces a very high risk of breast cancer which amounts to nearly 80% while in the population not carrying the mutation, one in ten women is affected.
One in 800 people (1) is a carrier of the mutation predisposing the onset of breast cancer in France. This mutation is sought if the family history suggests a risk of hereditary transmission cancer (age at onset of cancer, level of kinship, number of breast cancers in the family, etc.) (2)
Screening is offered by the attending physician who refers to a specialist so-called “referent” doctor at the turn of a consultation ofoncogenetics. It is this doctor who will take care of the woman throughout her life. A minimum period of reflection of eight days, associated with psychological treatment, is left to the patient to decide whether or not to carry out this test.
The search for the mutation is carried out in the genetics laboratory of the hospital of the specialized institute where the person is treated. The laboratories authorized to perform it receive an endowment from the Ministry of Health, so patients have nothing to pay (3).
If the mutation is found, the doctor suggests that his patient contact the members of his family who may be concerned by a screening.
What genes are these?
The genes affected by the mutation are the genes BRCA1 and BRCA2 for Breast cancer antigen. Both are implicated in breast and ovarian cancer in young women.
Their mutation is involved in 5% of breast and ovarian cancers. When it is found, it does not necessarily induce the development of cancer but increases the risk of its occurrence. Thus, the probability for a woman carrying a deleterious mutation in the BRCA1 or BRCA2 gene of having breast cancer during her lifetime is almost 80% and that of having ovarian cancer. from 45 to 50% for BRCA1 and from 10 to 20% for BRCA2 (4).
In the event of a genetic mutation, what monitoring is proposed?
A woman in whom the mutated BRCA gene has been detected will be followed for her entire life. The objective of this surveillance is to detect the early appearance of tumor tissues or cells in order to take charge of the disease as soon as possible.
From 20 years old, the referring physician will set up biannual clinical monitoring (palpation of the breasts and pelvic region).
From 30 years old, a annual follow-up MRI and mammography will be added and an ultrasound can be performed in case of dense breasts. An annual pelvic ultrasound will be performed from the age of 35 to detect the appearance of ovarian cancer.
Women who have not performed the screening but have a mother, an aunt, a sister carrying this mutation, will have exactly the same follow-up.
This surveillance does not prevent the development of cancer: this is why in France, 5 to 10% of women (5), carriers of the mutated gene, choose thepreventive breast removal every year.
In addition, depending on the context (menopause, desire to become pregnant), surgeons can offer their patients a removal of the ovaries (oophorectomy) which alone reduces the risk of getting breast cancer by 50%. Indeed, the estrogens they secrete promote the onset of cancer.
The operation is performed under general anesthesia. The surgeon removes the breast as a whole, including the areola (pigmented area around the nipple), the nipple. Thus, all glandular tissue will be eliminated to reduce the risk of cancer.
This ablation may be accompanied by immediate breast reconstruction with skin tattoo to recreate the nipple and its areola in an aesthetic way.
Removal of both breasts is fully covered by Social Security as well as breast reconstruction in this indication. A sick leave of two to four weeks is prescribed by the doctor.
Is the risk of this intervention zero?
As in any surgical procedure, the risk of postoperative complications exists and is estimated at 21% (6). This figure includes infections, bruises, acute or chronic pain, etc.
The doctor has a duty to inform his patient about the risks involved, in addition to the benefits for her health.
The final choice of intervention is up to the patient.
Is preventive mastectomy 100% effective?
According to Inserm, preventive removal of both breasts lowers the risk of developing breast cancer to 6.5% against 70% in the absence of an operation.
It may happen that cancer cells, not detected before the operation, have migrated to the lymph nodes located under the armpit. These cells can cause cancer in the area around the breast. In this case, the health professionals collectively decide on the continuation of the care (surgery, chemotherapy, radiotherapy).
Where can I find information on breast and ovarian cancer screening and prevention?