Breast cancer screening in women under 50 - why the pitfalls can outweigh the benefits

It is also an opportunity to reinforce the message of the importance of breast screening, the need of ongoing support for women going through the journey of breast cancer treatment, and to highlight the need for continued research, particularly for the more challenging breast cancer subtypes.

In many ways breast cancer treatment and care have been a success story with over 90% of women now surviving their cancer for 5 years or more. 

However, this leaves no room for complacency as around 11,000 people still die each year from the disease in the UK with almost 600 of these occurring in Wales.

One of the major successes behind the improvement in breast cancer outcomes has been the introduction of breast cancer screening which starts at 50. 

In Wales alone regular breast cancer screening has been shown to reduce mortality by around 25%. A question we often get asked at Cancer Research Wales is why can’t breast cancer screening be started earlier than the age of 50?

Breast cancer screening in women under 50: benefits versus harms

Breast cancer in women under the age of 50 is thankfully uncommon, although not unheard of. Typically, across the UK, breast cancer in women under 50 accounts for around 15-20% of all breast cancers, although the exact number can vary from region to region. 

The latest readily available data for Wales from 2019 shows that around 14% of the 2,790 women diagnosed with breast cancer that year occurred in women under the age of 50.

Every national screening programme must carefully balance the benefits it can bring versus the harms it may cause. Breast cancer screening exposes people to very small amounts of radiation. 

As breast cancer screening takes place between the ages of 50 and 70, with women called every 3 years, the risks of this radiation causing any harms is very low. Therefore, when conducted between the ages of 50 and 70 the benefits of breast cancer screening are greater than any possible harms.

Mammogram scans in younger women tend to be more difficult to interpret as the density of the breast tissue tends to be greater than breast tissue in older women of typical breast screening age. This may lead to women needing repeated scans and other further unnecessary investigations just to be sure. 

Also, there is no strong evidence to show that breast cancer screening in the under 50s would prevent further deaths from breast cancer, although this is an area of ongoing research.

Targeted breast cancer screening for women under 50

It is important to stress that breast cancer screening is available for certain women under the age of 50, especially if they have a history of breast cancer in the family or they are known to have inherited one of several faulty genes that can increase the risk of breast cancer developing at a younger age.

In women who have a family history of breast cancer genetic screening and testing have an important role to play. 

Women who feel they would benefit from genetic testing based on family history should first go to their GP and discuss any concerns they may have. GPs will be aware of all the centralised genetic services available, and if deemed appropriate can write a referral letter for follow-up investigations.

Following genetic testing and counselling an appointment can then be made with Breast Test Wales for breast screening in women under the age of 50, if thought beneficial for that individual. However, the whole process must start with an appointment with a GP.

The need for continued breast cancer research

Continued research is vitally important if we are to keep one step ahead of cancer. Research is the platform on which all vibrant health organisations continue to improve outcomes for their patients. 

Typically, genetic testing for breast cancer risk involves testing for several known risk genes such as BRCA1 and BRAC2 and TP53. 

Although research is continually discovering additional risk genes that may eventually be incorporated into routine genetic testing if the weight evidence shows a benefit.

Triple negative breast cancer (TNBC), which accounts for about 15% of all breast cancer, represents a cancer of unmet clinical need. 

TNBC disproportionally affects younger women, tends to be more aggressive and is more likely to spread to distant organs, and has less available treatments options than the other more common hormonal dependent breast cancer subtypes.

Cancer Research Wales recently funded projects with scientists in Swansea and Cardiff looking at new forms of treatment for TNBC and looking at methods to increase the potency of existing radiotherapy strategies used to treat the disease. 

At Cancer Research Wales we believe that a focus on research to treat the subtypes of breast cancer of unmet clinical need and the types that disproportionately affect younger women, will ultimately improve outcomes for all women.

Age should be no barrier to raising concerns

While breast cancer is uncommon in women it does happen, and any symptoms suggestive of breast cancer should be investigated, irrespective of age. 

A woman's age should not be the basis for ruling out the possibility of breast cancer even if the symptoms occur in women below the age of 50. It is best to rule out breast cancer rather than run the risk of leaving things too late, when the disease is much harder to successively treat.

Disclaimer: This blog is for information purposes and should not be taken as medical advice. If anyone has any concerns about breast cancer they should first speak to their GP or similar healthcare provider who will be only too willing to help where necessary.