How safe are breast screenings?

9 February 2014

how-safe-are-breast-screenings-mainAccording to Cancer Research UK each year around two million women undergo screening mammograms to check their breasts for the earliest signs of cancer. Although this helps save lives, there are potential drawbacks.

One disease women fear above all other is breast cancer. It is understandable, as almost 50,000 women develop the disease each year in the UK and 12,000 women will die from it, according to the NHS.



How likely am I to develop breast cancer?

“If you pick cancer up early it is less likely to spread elsewhere in the body and less likely to kill you.

“Smaller, earlier cancers can also be easier to treat, and less likely to need treatments such as chemotherapy.

“Certainly over the last 15 years I have been seeing fewer of the larger locally advanced breast cancers.”

When will I be offered a mammogram?

The breast screening programme, first rolled out nationally in the 1990s, aims to invite every woman aged 50-70 for breast screening every three years. It involves a mammogram which is essentially a breast X-ray.

“Some may find it a bit uncomfortable but it shouldn’t be too painful – if it is then you should tell the lady –  it will always be a lady – doing the mammogram and she should be able to try and make it more comfortable for you,” says Jessica Kirby, senior health information officer at Cancer Research UK.

Pros and cons

According to the NHS, between April 2009 and March 2010 almost two million women were screened and 15,500 were found to have breast cancer. Yet the NHS say that of those 15,500, around 4,000 will have been “over diagnosed” with changes that may or may not have become a cancerous tumour. Cancer Research UK says that 99 per cent will end up having surgery as a result.

“Pre-cancerous changes, called ductal carcinoma in situ, come in three stages,” says Mr Marsh.

“There is low grade which may never develop into cancer, intermediate which may develop into cancer in 10-15 years and high grade which is near to a proper cancer."

"The trouble is it is very hard to know which will and which won’t develop into a full cancer, with the potential to spread around the body.”

According to a report funded by Cancer Research UK and the Department of Health, The Benefits and Harms of Breast Cancer Screening, for every 10,000 women aged over 50 invited for breast screening over the next 20 years 43 deaths from breast cancer will be prevented, while 129 cases of breast cancer will be over diagnosed.

Over diagnosis is, however, not the only issue. As with any screening programme there can be false positives and there are also concerns of a very small risk that radiation involved in having the mammogram may actually cause cancer.

Is screening beneficial?

Having reviewed all the evidence in 2012 the expert panel brought together by Cancer Research UK and the Department of Health concluded screening is beneficial – the bottom line being that the UK breast screening programme saves around 1,300 lives a year.

To help those confused or concerned about screening, the NHS recently brought out a booklet called ‘NHS breast screening: helping you decide’ to help women make an informed decision about their options.

Jessica Kirby says, “If having read the leaflet women decide they still don’t want to undergo screening, then that is absolutely fine – women should not feel they have to do it.”

Other options

Some younger women – especially with a family history of breast cancer ‒ want the chance to undergo screening before they are 50. Normally the GP will send them to genetic counselling. If their risk is found to be high, they will usually be offered screening.

Those who do have mammograms or MRIs should still examine their breasts from time to time.

“Even women who go for screening should check for any unusual lumps, puckering, dimpling or changes to the nipples,” says Jessica Kirby.

Breast cancer can arise between screening mammograms so women should report anything new or different to their GP.

For more information on breast cancer screening visit our Cancer Centre or post any questions to our experts who will reply as soon as possible.