Breast cancer is the most common cancer among Singaporean women. More than 29% of all cancers diagnosed in women are breast cancers. 
Studies have shown that your breast cancer risk is higher if you have a first-degree or multiple relatives with breast cancer.
In hopes of avoiding future disease, a DxD reader with a strong family history of breast cancer wanted to know if she should go for a prophylactic mastectomy even though she has not been diagnosed with breast cancer. She shared that her mother and two of her aunts had the disease.
Family history does not necessarily mean that you will get breast cancer
People often think that as long as you have two or more first-degree relatives with breast cancer, it's a given that you will carry the genes that increase your risk, causing you to develop the disease at eventually.
However, that is not true. Most people diagnosed with cancer don't have a family history with the disease. Studies have shown that only 5%–10% of breast cancer cases are a result of a known inherited genetic defect. 
Start with genetic counselling
If you have a family history of breast cancer, Dr Evan suggests that you should first seek genetic counselling.
Genetic counselling is a consultation session where an experienced cancer genetics counsellor helps you evaluate and asses your family and your own cancer history. 
You might also have to take a blood test if genetic testing is required.
You should get yourself insured
Before getting any treatment or evaluation, Dr Evan advises that you should get your medical and hospitalisation insurance ready. This gives you peace of mind.
Removing your breasts before you are diagnosed
Prophylactic mastectomy is a surgery to remove one or both breasts, in hopes of reducing your risk of breast cancer. This is an option for those who are carrying genes that put them at very high risk of having breast cancer. 
A prophylactic mastectomy can greatly reduce your risk
There's a clear advantage of this operation: reduction in worry about breast cancer. Evidence confirms that there's an 85% to 100% reduction in the incidence of breast cancer after this procedure.
While it might seem like a straight-forward solution, Dr Evan highlights that this does not ensure breast cancer survival. There is still a chance that you might develop breast cancer.
You need to discuss it carefully with your doctor
This is a complicated decision, so don't rush into it. Dr Evan personally likes to go through all the options his patients before he/she makes a decision.
The alternative is close surveillance
If you prophylactic mastectomy is not something you are comfortable with, close surveillance is an option. Early detection of breast cancer can greatly improve survival rate.
Breast reconstruction can help with mastectomies
If you need to undergo a mastectomy, breast reconstruction is a good option to help negate the negative impacts.
Dr Evan explained that the same studies that report on the efficacy of prophylactic mastectomies also report about the negative impact on cosmetic result and sexuality if no reconstruction was performed.
Article medically reviewed by Dr Evan Woo.
1. National Registry of Diseases Office. et al. Singapore Cancer Registry Interim Annual Report Trends in Cancer Incidence in Singapore 2010-2014. May 2015.
2. Paraskevi Apostolou. et al. Hereditary Breast Cancer: The Era of New Susceptibility Genes. March 2013.
4. National Cancer Institute. et al. Surgery to Reduce the Risk of Breast Cancer. August 2013.