The use of artificial intelligence in breast cancer screening reduces the rate of a cancer diagnosis by 12% in subsequent years and leads to a higher rate of early detection, according to the first trial of its kind.
Researchers said the study was the largest to date looking at AI use in cancer screening. It involved 100,000 women in Sweden who were part of mammography screening and were randomly assigned to either AI-supported screening or to a standard reading by two radiologists between April 2021 and December 2022.
The AI system worked by analysing the mammograms and assigning low-risk cases to a single reading and high-risk cases to a double one by radiologists, as well as highlighting suspicious findings to support radiologists.
Mammography screening supported by AI reduced cancer diagnoses in the years after a breast screening appointment by 12%, according to the research, published in The Lancet. There were 1.55 cancers per 1,000 women in the AI-supported group compared with 1.76 cancers per 1,000 women in the control group.
More than four in five cancer cases (81%) in the AI-supported mammography group were detected at the screening stage, compared with just under three quarters (74%) in the control group, and there were also almost a third (27%) fewer aggressive sub-type cancers in the AI group compared with the control.
Dr Kristina Lång, from Lund University in Sweden and the lead author of the study, said that AI-supported mammography could help detect cancers at an early stage, but that there were caveats.
“Widely rolling out AI-supported mammography in breast cancer screening programmes could help reduce workload pressures among radiologists, as well as helping to detect more cancers at an early stage, including those with aggressive subtypes,” Lång said.
“However, introducing AI in healthcare must be done cautiously, using tested AI tools and with continuous monitoring in place to ensure we have good data on how AI influences different regional and national screening programmes and how that might vary over time.”
Breast cancer is the leading cause of death in women aged 35 to 50, with more than 2 million people globally diagnosed with the disease each year.
Although the study showed the apparent benefits AI could bring to mammography screening, the researchers do not support replacing healthcare professionals with AI, as screening still requires at least one human radiologist to perform the reading with AI support.
Dr Sowmiya Moorthie, a senior strategic evidence manager at Cancer Research UK, said the findings were promising but urged caution.
“Using AI to assist in reading mammograms can be more efficient, but there’s a concern that it can lead to missing some cancers. This study helps to address concerns, but the results are from a single centre, so more research will be needed to know for sure if this will help save lives,” Moorthie said.
She added: “With a growing number of people expected to be diagnosed with cancer in the years ahead, innovations like this will be vital to improving the NHS, but it’s important that they are properly evaluated to ensure people affected by cancer are helped rather than harmed.”
Simon Vincent, the chief scientific officer at Breast Cancer Now, said: “This first trial underlines the huge potential of AI to support radiologists in breast cancer screening. Screening is a vital tool for early detection, and the sooner the disease is found, the better chance of successful treatment.
“This study shows real promise for earlier diagnosis that could improve and save lives, which is why trials launched last year in the UK exploring the use of AI within the NHS breast screening system will be important in determining the safest and most effective way to use these tools to find more cancers early.”
