Artificial intelligence that scans primary care medical records to find hidden patterns has helped doctors detect significantly more cases of cancer.
The cancer detection rate increased from 58.7% to 66.0% at primary care physician practices using the artificial intelligence tool “C the Signs.” This tool analyzes a patient’s medical history to gather their past medical history, test results, prescriptions and treatments, as well as other personal characteristics that could indicate cancer risk, such as their zip code, age and family history.
It also urges GPs to ask patients about any new symptoms and, if the tool detects patterns in the data that indicate an increased risk of a particular type of cancer, then it recommends which tests or clinical pathways the patient should be referred to.
C the Signs is used in around 1,400 practices in England (around 15%) and was trialled in 35 practices in the East of England in May 2021, covering a patient population of 420,000.
The results, published in the Journal of Clinical Oncologyshow that the cancer detection rate increased from 58.7% to 66.0% as of March 31, 2022, while practices not using the system remained at a similar rate.
Bea Bakshi, a GP who created the system with colleague Miles Payling, said: “It could be a scan, an ultrasound, or they might need to be seen by a specialist in a clinic.”
Patients are monitored through the C the Signs system to remind doctors to check test results and referrals elsewhere. “Our system has detected over 50 different types of cancer,” Bakshi said. “The bottom line is that it’s not just about early diagnosis, but also faster diagnosis.”
Bakshi and colleagues also sought to validate the tool by evaluating 118,677 patients in a previous study, which found that 7,295 were diagnosed with cancer and 7,056 were successfully identified by the algorithm.
In cases where the tool concluded that a patient was unlikely to have cancer, only 239 of 8,453 patients received a confirmed cancer diagnosis within six months (about 2.8%). Bakshi developed the tool after meeting a patient in hospital who had been diagnosed with pancreatic cancer late and died three weeks later.
“It remained a problem for me,” he said. “Why are patients diagnosed with cancer so late?”
The UK has three cancer screening programmes – bowel, breast and cervical – but there are 200 different types of cancer that can be asymptomatic or cause symptoms that are easily confused with other conditions.
“Two-thirds of deaths are due to cancers that cannot be detected and are not screened for,” Bakshi said. “Patients visit their GPs three to five times before they are recognised as being at risk of cancer. GPs detect an average of eight cases of cancer a year.”
GPs use National Institute for Health and Care Excellence guidelines to make decisions about when to make a cancer referral.
“They’re pretty comprehensive guidelines, but no GP can remember them all,” said Peter Holloway, a GP who chairs the East of England Cancer Alliances Primary Care Group and co-author of the study.
“We know that many cancers present with vague symptoms and some are difficult to define and do not necessarily correlate with our guidelines.”
Holloway saw a patient in his 60s who had diarrhea and lower abdominal pain. “These are very common symptoms and not things that would lead to a referral to a physician for suspected cancer,” she said. But the C the Signs tool recommended a fecal test.
“The test came back positive, he was referred and it turned out he had colorectal cancer, which was diagnosed early and treated successfully,” Holloway said. “He’s doing well, but if we had followed the strict guidelines, he might not have been referred for several months.”
NHS England’s Long Term Plan for Cancer aims for 75% of all cancers diagnosed to be at stage one or two by 2028. The NHS is also investigating whether the Galleri blood test, which attempts to detect DNA from more than 50 different types of tumour, is effective. The trial began in September 2021 and 140,000 people have been tested.
Holloway said decision support systems like C the Signs were an important part of cancer screening, as well as improving patient awareness of different types of possible cancer symptoms and gaining better access to diagnostic technology such as CT and MRI scans.
Professor Peter Johnson, NHS England’s national clinical director for cancer, said: “Despite increased demand and pressure on services, record numbers of people are being screened and treated for cancer, and we are now diagnosing a higher proportion of cancers at an early stage, increasing people’s chances of survival.
“We know we have much more to do to help people with cancer get the care they need, and using the latest technology is an important part of our work to reduce waiting times and detect cancers earlier, such as teledermatology to diagnose skin cancers, or community lung care vans and home testing for bowel cancer.”