Detecting cancer before you ever get ill is a scientific breakthrough researchers around the world have been working towards for decades, but a new experimental study by the BC Cancer Agency may help make it a reality.
The agency will test the blood of 1000 healthy volunteers, aged 55 to 77, with no prior cancer history.
The study dubbed Cancer DNA Screening Pilot Study, or CANDACE, will examine the blood samples to see if researchers can detect any cancer DNA.
“It is ground-breaking because we are looking at using a blood test to detect cancer DNA in the blood stream,” said Principal Investigator Dr. Alan Nichol. “This is going to be used to screen for multiple different cancers at once. Other screening tests like mammography and colon cancer screening tests can only screen for one type of cancer at a time. So this is a real paradigm shift.”
At the core of the test is the technology developed by UBC and Boreal Genomics. It has been previously shown to detect cancer DNA present in very low levels in the blood.
“We have invented a very powerful technology for extracting a small number of cancer DNA molecules from the large amounts of normal DNA present in everyone’s blood,” said Dr. Andre Marziali, Chief Science Officer of Boreal Genomics and Professor and Director of Engineering Physics at UBC. “This enrichment for tumor DNA has enabled us to develop a highly sensitive test for tumor DNA in blood that promises to be a revolutionary cancer screening tool.”
Researchers say the technology can detect 96 common mutations seen in at least eight cancer types including lung, breast, colorectal, ovarian, pancreatic, bladder, endometrial cancers and melanoma, and may detect other cancers as well.
The BC Cancer Agency says for many types of cancer, early detection means more treatment options and better outcomes.
If effective, the appeal of the new test would be in its simplicity and inexpensiveness. It also promises to detect very early signs that might otherwise go undetected until symptoms develop.
“Some of the other tests, like a Pap test, are invasive or in colon cancer screening, for example, the person being screened needs to collect some stool, which people don’t find very pleasant,” Nicol said. “Mammography also has a reputation for being uncomfortable and people don’t like that. So I think people would be very interested in a screening test that would be simply a blood test.”
As for the commercial use, Nichol says it’s too early to estimate how much the blood test might cost or how often it could be administered.
“In the use of screening tests, the timing of it is really important and because of the costs associated, they can’t be done monthly,” he said. “It might be possible to do a test like this once a year or maybe every six months, but it would depend to a great degree on the actual price when it enters the market in the future.”
The agency will use volunteers who have previously agreed to be a part of the BC Generations Project, the largest-ever health study of British Columbians involving nearly 30,00 participants. Participation in the CANDACE study is by invitation only, however.
Participants who have a positive test result will be examined further using standard-of-care diagnostic methods, including medical imaging, to confirm whether the blood test has correctly indicated the presence of a cancer.
Nicol and his colleagues will also be focused on determining whether the test produces any false positives – positive results in patients who don’t actually have cancer.
The study is expected to be completed by September 2017.
“There will have to be a bigger study done after this one to fully characterize this screening test,” said Nichol. “And from information in that future study, we might be able to learn more about the intervals that are required to do the testing and how often we would find cancer if the test is repeated.”
Nicol says they might be looking to recruit more participants in similar studies in the future, potentially from the general public.