Large-scale research is underway to investigate the effectiveness of the largest ever 'blood test that can detect various cancers'



In recent years, medical technology using AI has made great progress, and

blood tests that can detect more than 50 types of cancer have also been developed. Meanwhile, the National Cancer Institute (NCI) is planning a large-scale study to investigate the effectiveness of cancer screening tests using blood samples, and the science of the academic journal is NCI's cancer We interviewed Philip Castle , the prevention director.

'The complexities are staggering.' US plans huge trial of blood tests for multiple cancers | Science | AAAS
https://www.science.org/content/article/complexities-are-staggering-us-plans-huge-trial-blood-tests-multiple-cancers

President Joe Biden of the United States has complained that ' the cancer mortality rate will be halved in the next 25 years, ' and is working to promote cancer screening, support the development of treatment methods, and promote public-academia-private partnerships. As part of this, NCI is conducting research on the effectiveness of 'cancer screening tests using blood samples,' which has become more realistic with the development of AI.

Startups such as Grail and Exact Sciences are already developing blood tests to detect cancer, and Grail is offering $ 949 to people over the age of 50 and those at high risk. increase. To test the effectiveness of these 'blood tests to detect cancer,' NCI advisors funded $ 75 million in a (PDF file) document released in June 2022. We support the introduction and conducting pilot research targeting more than 24,000 people in four years.

As a first step towards a pilot study of blood tests for cancer, NCI will take blood samples from patients who are already known to have cancer and those who are not considered to have cancer. We plan to verify the startup's claims. After that, a pilot clinical trial will be started in 2023 or 2024, and if this trial is successful, it will proceed to a larger follow-up study.



Science interviewed NCI's Director of Cancer Prevention, Castle, about NCI's ambitious project for cancer blood testing. Below are the science questions and Castle's answers.

Q: What does NCI want to learn from pilot research?
A: We need to understand how to handle blood and how to send blood to the company and receive the results. We need to know in clinical studies whether we can set up a control group that receives only normal care, but while it is unclear whether blood tests will actually benefit, setting up a control group breaks the contract. It may be.

Q: Many companies are developing more than 20 tests, how do you verify them?
A: The results of cancer blood test studies need to be peer-reviewed, the data publicly available, and show that the results are reproducible. They must be able to determine inspection parameters and algorithms, and must be capable of adequate testing. Therefore, only a few tests may really be available for clinical trials.

Q: Are there any things that can be clearly stated to be included in pilot research, such as Grail and Exact Sciences?
A: First of all, it's unclear if Grail or Exact Sciences wants to be included in the pilot study. And given that Grail already offers direct testing to consumers, there may be no incentive to participate in the study. Exact Sciences also seems to be considering its own clinical trials.



Q: What will the 'large-scale long-term clinical trial' look like after the pilot study?
A: Perhaps there will be about 75,000 people in each control or experimental group. Therefore, if three blood tests are tested and one control group is set up, about 300,000 people will be enrolled. We believe it will take about 7-8 years to complete the clinical trial. There has never been a study of such a large cancer screening test in the United States.

Q: Past studies have estimated that 1% of subjects have a positive test for cancer, but do these people actually have cancer?
A: In past positive studies, one-third of people who tested positive found nothing, and one-third had benign tumors that were not cancer, and one-third. I was actually suffering from cancer.

Q: What do you think about the advisor at the NCI meeting who was concerned that a blood test for cancer would be the second move of a PSA (prostate specific antigen) test? (PSA is used as a marker for prostate cancer, but it is controversial because it is often misjudged by harmless prostate tumors.)
A: There are many possible harms. Blood tests for cancer may reduce advanced cancer, but they cannot reduce mortality itself, and they may find tumors that do not need to be treated like PSA tests. .. We are also concerned about whether those who actually get a positive result will be seen later and what the risks will be in the future. In addition, a negative cancer blood test can negate the benefits of a blood test if some people do not have a standard cancer screening.

Q: Why move the project forward when there are still doubts about blood tests for cancer?
A: There are no screening tests for deadly cancers such as pancreatic cancer or ovarian cancer, so it's nice to be able to do that with a blood test. But we must set ourselves aside, strive to evaluate these techniques, and be able to speak confidently about what we can and cannot do.



in Science, Posted by log1h_ik