Family history of breast cancer: Should I take HRT? Factsheet

This factsheet is for you if you have a family history of breast cancer and are wondering whether HRT poses any particular risks for you. If you would like to know more about your personal risk of inheriting breast cancer because you have a family history, speak to your doctor.

If you have had breast cancer, please see our booklet titled ‘Been through Breast Cancer: Did someone mention menopause?’

What is HRT?

HRT stands for Hormone Replacement Therapy and this is the umbrella term for hormonal treatments that work to relieve symptoms of the perimenopause and menopause. HRT replaces the ‘missing’ hormones that decline in the years around the time of the menopause.

Low levels of hormones can cause symptoms such as hot flushes, night sweats, anxiety, mood swings, brain fog, and vaginal dryness and discomfort. Living for years with low hormones increases your risk of the bone weakening disease osteoporosis, and heart disease, as well as other conditions such as type 2 diabetes, dementia, bowel cancer and depression.

HRT helps improve symptoms of the perimenopause and menopause, and it also helps prevent the diseases mentioned from developing in the future.

What is in HRT?

There are different types of HRT and different ways to take it. The two main hormones that make up HRT are estrogen and progesterone. Estrogen is the key hormone to help improve your symptoms (as most of them are usually caused by a lack of estrogen). The preferred way to take estrogen is through the skin in a patch, gel or spray.

Progesterone (or a progestogen) is usually recommended for women who still have their womb and are taking estrogen, this is to help keep the lining of the womb thin and healthy (as estrogen can thicken it). You can take this hormone in tablet form or have a Mirena coil inserted into your womb which can remain for 5 years.

Testosterone is a third hormone which some women will need for additional help with symptoms of low libido, lack of energy and poor concentration.

What are the risks of HRT for all women?

For the vast majority of women, the benefits from taking HRT outweigh any risks. The risks of HRT depend on the type you are given and also other factors such as your age and general health. Because there are different factors at play in determining an individual’s risk of breast cancer, it’s so important to have a personalised consultation with your doctor to discuss your actual risks.

Many women worry about breast cancer when taking HRT, but most types of HRT do not actually increase the risk of breast cancer. Some studies have shown that women taking combined HRT containing both estrogen and a progestogen (which is a synthetic progesterone) may be associated with a very small increased risk of breast cancer.

The increased risk is related to the type of progestogen in the HRT and not the estrogen. Taking micronised progesterone (the body identical progesterone) has not been shown to be associated with an increased risk of breast cancer.

Even for women taking the synthetic progestogen, the risk is very low and is actually less than the increased risk of breast cancer associated with drinking a couple of glasses of wine each night, or from being overweight. No studies have shown that any type of HRT increases the risk of a woman’s death from breast cancer.

If you have had a hysterectomy in the past, and are just taking estrogen without a progestogen, you actually have a lower risk of breast cancer than if you did not take HRT at all. There is also no increased risk of breast cancer in women who take any type of HRT when they are under the age of 51 years.

If you take estrogen in tablet form, you have a small increased risk of developing a blood clot, but this risk is not
present if you take estrogen through the skin in a patch, gel or spray.

Should I take HRT if I have a family history of breast cancer?

Most women will have a family history of breast cancer in their family because it is a relatively common disease. However, it is estimated that only about 10% of the breast cancers that are diagnosed every year have a genetic
or familial cause.

Women with a family history of breast cancer should discuss it with their doctor if they are considering HRT. A woman’s lifetime risk of getting breast cancer is 1 in 7. This means that 1 in 7 women taking HRT will get breast cancer – not because of the HRT, but because they would have developed it anyway.

There is no strong evidence that having a family history of breast cancer puts you at any higher risk of getting breast cancer if you take HRT, compared to women who do not have a family history of breast cancer. There is some evidence that women with a family history of breast cancer who take HRT actually have a lower future risk of developing breast cancer compared to women not taking HRT.

This means that women with a family history of breast cancer, including those women with a BRCA gene, can still usually take HRT safely. As there are many health benefits of taking HRT, women can usually take HRT for ever, so do not have to stop taking it at a certain age or after a specific length of time.

Most women who have a family history of breast cancer do not go on to develop breast cancer, regardless of whether they take HRT or not.

Some final advice to remember…

To lower your risk of breast cancer:

­- Stay a healthy weight
– ­Take regular exercise
­- Don’t smoke
­- Limit alcohol to as little as possible

And remember to look at and feel your breasts regularly, for anything that’s different to normal.