Nearly 300,000 women could benefit from a drug to reduce their risk of developing breast cancer, according to NHS officials.
Some 289,000 postmenopausal women in England with a moderate or high risk of breast cancer will be offered the hormone therapy 'anastrozole' to help prevent them from developing the disease.
Trials have shown that the drug reduces breast cancer cases by 49% over 11 years among eligible women.
Officials have estimated that if 25% of eligible women in England take up the offer – and half of those take the drug for the recommended five years – then 2,000 cases would be prevented over their lifetimes.
Scientists have found that as well as treating breast cancer, anastrozole can also prevent cases, with protective effects lasting years after a woman has stopped taking the drug. While it is usually used to treat breast cancer, it has been "repurposed" to also help with prevention.
The moves adds to the NHS’s armoury of preventative breast cancer medication, with tamoxifen and raloxifene already licensed to prevent breast cancer.
"It’s fantastic that this vital risk-reducing option could now help thousands of women and their families avoid the distress of a breast cancer diagnosis," says NHS chief executive Amanda Pritchard.
"Allowing more women to live healthier lives, free of breast cancer is truly remarkable, and we hope that licensing anastrozole for a new use today represents the first step to ensuring this risk-reducing option can be accessed by all who could benefit from it.
"This is the first drug to be repurposed through a world-leading new programme to help us realise the full potential of existing medicines in new uses to save and improve more lives on the NHS.
"Thanks to this initiative, we hope that greater access to anastrozole could enable more women to take risk-reducing steps if they’d like to, helping them live without fear of breast cancer."
Anastrozole is taken as a 1mg tablet, once a day for five years. It works by cutting down the amount of the hormone oestrogen that a patient’s body makes by blocking an enzyme called aromatase. The most common side effects of the medicine are hot flushes, feeling weak, pain/stiffness in the joints, arthritis, skin rash, nausea, headache, osteoporosis, and depression.
Aside from advancements in medicines, people sharing their stories with breast cancer has also helped to raise awareness and save lives. In September, Sarah Beeny reminded women of the importance of early diagnosis a year into her own journey with the disease.
The TV presenter, 51, was diagnosed with breast cancer in August last year, but having undergone a double mastectomy and chemotherapy was given the all-clear in April this year.
Beeny appeared on Good Morning Britain to discuss life since her diagnosis and told hosts Susanna Reid and Ed Balls that despite a "difficult year" she feels "very lucky".
"Difficult things have happened to me all my life," she said. "And the way I handle those is to use it as the compost for the next stage of success. It isn't always easy but I'm glad it isn't always easy because that teaches you that light and shade is what you need in life."
The property expert went on to say that while the year has been a "little bit gruelling" she now feels "very fortunate".
"I'm very lucky to live in the UK with the amazing treatment and research and to be in the year it is and not 40 years ago," she says. "I know that other people aren't as fortunate as me, but I feel that speaking out about it might just make one person go to the doctor and the earlier the diagnosis, the better the outcome."
Other celebrities who have discussed their own cancer experiences and encouraged others to check their breasts include Anne Diamond, who said she had received the diagnosis the same day as finding out she was to be awarded an OBE, Kelly Hoppen, who missed eight years of mammograms, and Deidre Sanders, who shared last year that she had been diagnosed with high grade ductal carcinoma in situ after missing a routine mammogram.
So, to keep pushing awareness of the condition forward, here's what you need to know about breast cancer symptoms and the different types.
Breast cancer symptoms
Breast cancer is the most common type of cancer in the UK. According to charity Coppafeel!, symptoms include:
Changes in skin texture (including puckering and dimpling)
Swelling of the armpit and around the collarbone
Lumps and thickening around the breast
Constant or unusual pain in the breast or armpit
A sudden or unusual change in size or shape
Nipple inversion or nipples that change direction
A rash or crusting of the nipple or surrounding areas
Types of breast cancer
There are several different types of breast cancer, but the NHS divides them into two categories.
1. Non-invasive breast cancer (carcinoma in situ)
This refers to cancer found in the ducts of the breast which has not spread into the breast tissue surrounding them. It is usually found during a mammogram and rarely shows as a lump.
2. Invasive breast cancer
This refers to cancer cells that have spread into the breast tissue and is the most common type of breast cancer.
Breast cancer risk factors
Breast cancer is most common in women over the age of 50 who have been through menopause.
2. Family history
People whose close relatives have had breast cancer may have a higher risk of developing the disease themselves.
Oestrogen can sometimes stimulate breast cancer cells, and the risk of developing breast cancer may increase slightly with the amount of oestrogen your body is exposed to.
4. Lifestyle factors
Certain lifestyle factors, such as being overweight or obese and drinking alcohol can increase the risk of developing breast cancer.
Exposure to radiation, for example through medical treatments, can slightly increase the risk of developing breast cancer.
When to get help for breast cancer symptoms
If you do feel something, you don't necessarily need to be alarmed, as breast changes can happen for any reason, with most lumps not being cancerous.
However, if you experience unusual breast changes and you're not sure of the cause, it's important to book an appointment with your GP as soon as possible to rule out breast cancer.
It is important to see your doctor if you notice any unusual changes in your breasts, even if you are feeling well.
In order to catch these changes, people are encouraged to do monthly breast self-examinations and schedule regular breast exams and mammograms if you are eligible.
How to check your breasts
The NHS recommends looking at your breasts and feeling each breast and armpit, up to your collarbone. This might be easier to do in the bath or shower, using soapy water to make the process a little easier.
Alternatively, you could look in the mirror, swapping between having your arms by your side and having them raised.
Before checking, it's important to remember that everyone's breasts are different, whether you might be on your period (which can make them tender and lumpy), post-menopause (which can make them feel softer) or have one larger than the other.
The NHS Breast Screening Programme has produced a five-point plan:
Know what's normal for you
Look at your breasts and feel them
Know what changes to look for
Report any changes without delay
Attend your routine screening if you're 50 or over
Breast cancer treatments
There are two main types of breast cancer surgery. Breast-conserving surgery is where the cancerous tumour is removed, while a mastectomy is where the whole breast is removed.
Controlled doses of radiation are used to kill cancer cells. This treatment is usually given after surgery and chemotherapy to kill any remaining cancer cells.
This treatment involves taking an anti-cancer medicine to kill cancer cells, usually administered through a drip straight into a vein. However, it can also be given in tablet form.
4. Hormone therapy
Hormone therapy lowers the levels of oestrogen or progesterone hormones in the body to stop them from stimulating cancer cells. It is usually given after surgery and chemotherapy, and most people will have to take it for five years or more after surgery.
For support you can call Breast Cancer Now on 0808 800 6000.
Additional reporting PA.
Watch: How to check your breasts for lumps