Global Health Asia-Pacific July 2022 - Page 51

Blood tests could help improve cancer screening .
Such an approach might be game-changing especially for cancers that don ’ t have reliable screening programmes , like those that arise in the pancreas , which are often deadly because they ’ re diagnosed at a late stage .
“ This quick and simple blood test could mark the beginning of a revolution in cancer detection and treatment here and around the world ,” said NHS England ’ s Chief Executive Amanda Pritchard , according to the BBC .
The bad news , however , is that Galleri had a low detection rate of 16.8 percent with stage I cancers , which are usually localised in one tissue and therefore easy to treat , while its accuracy rates only increased with tumour staging , reaching about 90 percent in stage IV , according to the Circulating Cell-Free Genome Atlas study . This casts doubts over how useful it would be since the target population of a screening test is more likely to have early-stage cancers than advanced ones .
It ’ s also uncertain to what extent such a test would benefit patients as not all cancers picked up by liquid biopsy will necessarily require treatment .
“ Galleri is not covered by insurance or endorsed by national guidelines because clinical utility has yet to be demonstrated . We have to study the frequency of testing and establish plans for follow-up if the blood test detects a cancer signal , but no cancer is identified . There are still a lot of questions to answer , � Dr Minetta C . Liu , Co-Director of the Genomics in Action Strategic Priority at the Mayo Clinic , told The ASCO Post .
Professor Shaw agrees that more studies are needed to back up the use of blood tests as a screening tool and believes the ongoing NHS-Galleri trial in the �ational Health Services in the �� will offer some good answers .
The study aims to recruit 140,000 healthy people to collect their blood samples and is looking into the use of this new blood test to see if it can help NHS doctors to detect cancer early when used alongside existing cancer screening in a way that provides patients with better survival chances .
“ We need to see what these studies deliver ,” she emphasised , noting that blood tests may be more likely to be useful screening tools in specific areas where they can be added to established screening programmes , like those for breast and colorectal cancers , instead of providing a single and effective method for multiple cancers . n
“ This quick and simple blood test could mark the beginning of a revolution in cancer detection and treatment here and around the world .”
GlobalHealthAsiaPacific . com JULY 2022
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