My mother/ sister had breast cancer and I am worried that I may also get breast cancer. What are the chances that I may also get breast cancer?
The risk of developing breast cancer is increased 1.5 to 3 times if you have a mother or sister who had breast cancer compared to those who don’t have any family history. However, the majority of women who get breast cancer do not have any family member who has the disease, and only around 20% of women have a true hereditary predisposition to get breast cancer.
Can I be tested to find out whether I have an increased chance to get breast cancer?
A simple blood test can be taken to find out whether you have certain genes that can predispose you to have a breast cancer such as BRCA 1 and BRCA 2 gene. Mutations in these genes account for only around 20% of those tumours with familial predisposition.
For whom is genetic testing for BRCA1/BRCA2 highly recommended?
Genetic testing for BRCA1/BRCA2 gene mutation in women is particularly helpful if there are*
Three or more cases of breast/ovarian cancer in a family
Two breast cancer cases in a close relative with one diagnose younger than 50 years
Two breast cancer cases in a family diagnosed younger than 40 years
Male breast cancer in the family
Breast and Ovarian cancer in the same patient in a family
* Balmana J et al. BRCA in breast cancer: ESMO Clinical guidelines. Ann Oncol. 2011;22(6):31-34.
What are BRCA 1 and BRCA2 gene mutations?
The cells in our body have multiple DNA and RNA. When this DNA and RNA multiply, there can be some damages. BRCA1 and BRCA2 genes help to repair these damages, help prevent cancer and so they are called tumour suppressor genes. When these genes under go mutation, the damages in the DNA and RNA are not mended and result in cancer.
What cancers are produced by BRCA1 and BRCA 2 gene mutations?
| Cancers produced by BRCA1 gene mutation |
Cancers produced by BRCA2 gene mutation |
| Breast |
Breast |
| Ovary |
Ovary |
| Fallopian Tubes |
Colon |
| Prostate (Men) |
Pancreas |
|
Prostate (Men) |
What is the significance of BRCA1/BRCA2 genes with regards to breast cancer?
BRCA 1 and BRCA 2 mutation carriers have a greater than 80 % lifetime risk of breast cancer and if diagnosed with breast cancer they have a 40 % risk of breast cancer on the other side. Of the two gene mutations, compared with other women who get breast cancer, the women with BRCA 1 mutations have tumours
That are higher gradetumours (they grow and spread faster)
Present early at a younger age
May not have hormone receptors that make them suitable for endocrine therapy
How frequent are the BRCA 1 and BRCA 2 mutations in the population?
BRCA 1 and BRCA 2 mutations are prevalent approximately among 1 in every 300 women.
I have tested negative for the gene mutation test. Does it mean that I will not develop breast cancer?
The gene mutation test looks out only for certain genes which produce breast cancer like BRCA1, BRCA2, PALB2, CHEK2 and ATM genes. There are many more genes which can cause breast cancer which have not been found to date. Breast cancer is also more common in women without ant family history. So a negative test does not guarantee that you will not get breast cancer and you would need to get your breasts regularly screened for breast cancer just as everyone else would which is
Monthly self-breast examination
Annual Screening by Mammogram and palpation by the doctor
If I test positive for these gene mutations what are my options to prevent breast cancer?
Frequent Surveillance As the patients have a high risk of getting breast cancer, frequent surveillance is done to detect the breast cancer at an early stage. This method is adopted by many women who are not yet ready for surgery and they want to complete their family before surgery which is done by
- Monthly self-examination by the patient
- Mammogram/MRI screening every 6 months ( As the young breasts are quite dense mammograms may not pick the tumours)
- Examination by the doctor every six months
Chemo prevention with Tamoxifen Tamoxifen is a drug which acts against the estrogen receptors in the breast helping to reduce the rate of breast cancer. Tamoxifen helps to reduce the risk of getting a tumour in the opposite breast after one breast is affected. However, it has not been shown to help much in reducing the risk of getting breast cancer in the first instance.
Bilateral mastectomy(removal of both breasts) and reconstruction of the breasts Removal of both the breasts has shown that there is 90% reduction in breast cancer and 95% reduction of breast cancer if the ovaries had been removed earlier. Once they have been removed it is better to reconstruct the breasts at the same time in the same operation because
- The patient never worries that she didn’t have a breast, wakes with a breast, feels happier and is more confident
- Reconstructing immediately during the same operation preserves the skin and the reconstruction looks nicer for the women
What are my options for reconstruction after removal of both breasts?
The options for breast reconstruction can be broadly divided into
Autologous reconstruction (using the patients own tissue)
Using the patient's own tissues are the best form of reconstruction as they look better and feel better. Unlike implants, they don’t need to get replaced every ten years. Using microsurgery, the tissues are taken along with its blood supply and connected to the blood vessels in the chest or the axilla to make similar breasts. The doctor will discuss with you your best choices and the tissue along with its blood supply can be taken from
- Lower abdomen ( DIEP flap)
- The Inner thigh (TUG Flap)
- The lower Back (LAP flap)
- Latissmus Dorsi Flap (LD Flap)
Implant reconstruction Many women may not have enough tissue for reconstruction, may not be suitable for autologous reconstruction due to several health issues and some women may not prefer a surgical incision or a scar in a site other than the breast. For some, it could just be a personal preference. For these women, reconstruction with breast implants could be done. For more information regarding this please click here.
Combination of autologous reconstruction and Implant Reconstruction This method of using implants along with the patients own tissues are done when the patient doesnt have adequate tissue to reconstruct their breast to achieve symmetry. Example Latissmus dorsi flap and DIEP flap are often combine with implants to give better symmetry to the patient.
I am undergoing treatment for breast cancer in one breast. I just did my genetic testing and found that I have BRCA1/BRCA2 gene mutation. I am now worried that I may get breast cancer in the opposite breast. What can I do?
The chance of having breast cancer in the opposite breast is about 40% if you have breast cancer in one breast. The hormone therapy that may be given for the first breast cancer may give some protection for breast cancer. However, there is always a high risk and hence prophylactic mastectomy and reconstruction of both the breasts can be done at the same time.
What are the other genes that have been reported to cause breast cancer?
The other genes to have been reported to cause breast cancer are PALB2 gene mutation, CHEK2 mutation and ATM gene mutation. The risk profiles of the causative breast cancer gene mutations are as follows
| Gene |
Risk of Breast Cancer (%) |
Increased Relative Risk |
Age at Which Prophylactic Surgery is Considered (yr) |
| BRCA1 |
>80 |
10 |
25 |
| BRCA2 |
>80 |
10 |
25 - 30 |
| PALB2 |
34 - 58 |
2 - 4 |
35 - 40 |
| CHEK2 |
20 - 40 |
2 - 4 |
35 - 40 |
| ATM |
20 - 40 |
2 - 4 |
35 - 40 |
What are my chances to develop ovarian cancer if I am affected with BRCA1 and BRCA2 gene mutations?
The risk of developing ovarian cancer by the age of 70 in patients with BRCA1 gene mutation is 33% and those with BRCA 2 gene mutation is 11%. Women with BRCA 1 gene mutation have a sharp increase in developing ovarian cancer beyond the age of 40 and women with BRCA2 gene mutation have a sharp increase in developing ovarian cancer by the age of 50 years.
How can I prevent getting ovarian cancer if I have BRCA1/BRCA2 gene mutations?
It is recommended that you have frequent checkups every 6 months from the age of 25 to detect ovarian cancer early by the following
Pelvic examinations by your gynaecologist
CA-125 levels in the blood
Trans vaginal Ultrasound
Removal of both the ovaries along with the fallopian tubes is recommended after the age of 35 and after when childbearing decisions are complete.
I have just found out that I have tested positive for BRCA1 and BRCA2 gene mutations. Do I need to inform my family?
It is recommended that you inform your family members as well as they may have the same gene mutation. Testing for the gene mutation early may help them prevent having cancer and the treatment of cancers such as chemotherapy, radiotherapy and hormone therapy. However, the decision to test themselves should lie with themselves and not be forced on.
Are men spared from the effects of BRCA1 and BRCA2 gene mutations?
Men are not spared from the effects of BRCA 1 and BRCA 2 gene mutations as they can also develop breast cancers. The risk for developing breast cancers is higher especially for those with BRCA2 gene mutations. Breast cancer can be detected in men by self-examination and if they detect any swelling, nipple discharge, nipple asymmetry they need to see the doctor immediately to rule out breast cancer.
