A study looking at breast cancer risk during screening (PROCAS)

This study found that it was possible to use breast density and genetic changes to help predict people’s breast cancer risk more accurately. 

Study design
The study was for women invited for NHS breast cancer screening for the first time. It included people in the Manchester area. 

57,000 people took part. 

They completed a questionnaire about:

• their general health
• when their periods started
• any pregnancies
• whether they had been through the menopause
• family history of breast cancer 
• diet and lifestyle

Everyone had a mammogram that a specialist doctor checked in the usual way. 

A researcher also looked at the mammogram to work out breast density. Having more dense tissue increases the risk of breast cancer. This is because dense breast tissue has less fat and more breast cells and connective tissue.

Some people also gave a sample of spit (saliva). The team used these samples to look at DNA  and for any gene changes (mutations ) people may have had.

Results
The researchers analysed all the information they collected to work out each person’s risk of developing breast cancer. They looked at their risk of developing breast cancer within 10 years. They divided them up into 3 different risk groups:

• low risk 
• average risk 
• moderate to high risk

The team found the method they used was accurate to do this.

The results showed that a small number of women had a higher than average risk of breast cancer. This group were invited to discuss ways to reduce the risk with a specialist. People who had an average or below average risk were sent a letter to let them know their risk. Everyone had a chance for further discussion with the research team if they so wished.

The team worked out that for about 7 out of 10 people (70%), 3 yearly screening is often enough and works well. They found this group of people had an average or below average risk of developing breast cancer. And very low rates of advanced breast cancer. This is cancer that is very big or has spread to the lymph nodes . 

Conclusion
The study team concluded that adding breast density and DNA information improved screening. This information alongside usual screening techniques gave a clearer picture about individual risk. And could be useful for the NHS breast screening programme. 

The researchers say this research might help to tailor breast screening and identify those at greater risk of developing breast cancer. More work needs to be done to find out about including it as part of the screening programme. For example they need to look at cost. And at the benefit of telling women their breast cancer risk as they don’t want to worry them. 

Other research
We have information on the trials database about 2 other studies that are linked to this one. 

One is a follow on from this study. The study is called BC-Predict. The team want to find out if it’s possible to make the risk assessment a part of the breast screening programme. It closed in June 2021 and we hope to add the results when they are available. 

The other is called the PROCAS lifestyle study. It is looking at personalised information about breast cancer risk. And whether it increases the number of women who can follow a diet and exercise weight loss programme.

More detailed information
There is more information about this research in the reference below. 

Please note, this article isn’t written in plain English. It has been written for health care professionals and researchers.

Journal articles
Improvement in risk prediction, early detection and prevention of breast cancer in the NHS Breast Screening Programme and family history clinics: a dual cohort study.
D. Evans and others
Programme Grants for Applied Research, 2016. Volume 4, Issue 11, 

Where this information comes from    
We have based this summary on the information in the article above. It has been reviewed by independent specialists (peer reviewed ) and published. We have not analysed the data ourselves. As far as we are aware, the link we list above is active and the articles are free and available to view.