From this week, women in England and Wales who have an increased risk breast cancer because of their family history can be prescribed a daily pill to reduce their risk.

The drugs tamoxifen and raloxifene can reduce a woman’s risk of breast cancer by between 30% and 40% when taken daily for five years.  New guidelines from NICE (National Institute for Health and Care Excellence) recommend that the NHS should offer these drugs to women who have a high risk of breast cancer.  NICE also recommends that doctors consider offering them to women who have a moderately increased risk of breast cancer.

It’s thought that up to half a million women could be offered the drugs. This is the first time any country in Europe has offered drugs to healthy women to reduce their risk of breast cancer.

Until now, the only treatment option available to women who wanted to reduce their risk of breast cancer was surgery to remove the breasts or ovaries.  But this type of surgery is a major step to take and is only suitable for a small number of women with a high risk of breast cancer. The new guidelines mean that many more women will be able to reduce their risk by taking a tamoxifen or raloxifene pill every day for five years.

Scotland and Northern Ireland

The Scottish government says women at increased risk because they have two or more family members who‘ve had breast cancer will be offered tamoxifen.

It’s likely that Northern Ireland will soon follow suit.

Breast cancer and family history

Breast cancer is the UK’s most common cancer, with around 50,000 women and 400 men diagnosed with it every year. On average, women in the UK have about an 11% chance of developing breast cancer in their lifetime.

Some women have a higher risk of breast cancer because other members of their family have had it. This is called a family history of breast cancer.

Most breast cancers (about 80%) aren’t linked to a family history. But, the more members of a family who have breast cancer, and the younger they were when diagnosed, the greater the chance of a family link.

A family history of cancer is based on your close relatives (first-degree relatives and second-degree relatives). First-degree relatives are your parents, brothers, sisters and children. Second-degree relatives are your grandparents, uncles, aunts, nieces and nephews.

Women who have any of the following may have an increased risk of breast cancer because of their family history:

  • One first-degree relative who developed breast cancer under the age of 40
  • One first-degree male relative who developed breast cancer
  • One first-degree relative with cancer in both breasts
  • Two close relatives (one of whom is a first-degree relative) on the same side of your family who developed breast cancer under the age of 60
  • Three relatives on the same side of your family who developed breast cancer at any age
  • Breast and ovarian cancer on the same side of the family.

If you’re worried about your family history of cancer, see your GP. You may also want to use OPERA. OPERA is an online self-assessment tool that gives you a personalised assessment of your genetic risk, with further information and support.

If your family history suggests you may be at higher risk of breast cancer, your GP will refer you to a clinic for specialist advice. They will assess your lifetime risk. It may be about the same as the average for the UK (about 11%), or it may be moderate or high. Moderate risk means your lifetime risk is greater than 17% but less than 30%. High risk means a 30% or greater chance of developing breast cancer in your lifetime.

Weighing everything up

Tamoxifen and raloxifene can reduce the risk of breast cancer by 30%–40%. But they can also cause side effects similar to the menopause such as hot flushes, vaginal discharge, vaginal dryness, urinary problems and weight gain. They also increase the risk of blood clots and womb cancer. For most women at high risk, the benefits probably outweigh the risks, but women at moderate risk may have to think more carefully if they’re offered this treatment.

Healthcare professionals at a specialist genetics service should talk to you about all the possible treatments. They can explain the possible benefits and side effects of each treatment. They can also give you an estimate of how much each treatment might reduce your risk so that you can make a decision about whether to go ahead with any of the options.

We hope the information in this blog has answered any questions you may have about the new guidelines. If you have any other questions or concerns about breast cancer, you can talk them through with our cancer support specialists.

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