Multi-cancer early detection tests for general population screening: an updated systematic literature review

Project overview 

This is the first of a series of projects on MCD technologies. Given the complexity of the multi-cancer context, we are evaluating the evidence around the full range of these technologies, working with key stakeholders, to inform decision making across the different pathways in which they could have a role. This programme of work will involve a number of components, including updating an existing evidence synthesis, the construction of living evidence maps and the development of new evidence syntheses evaluating the use of MCDs in different populations at different points on the detection and diagnostic pathway. The aim of this project is to update a previously published systematic review on the accuracy and clinical effectiveness, acceptability and feasibility of blood-based MCED tests for population-based screening.

Status: ongoing

Contact: sofia.dias@york.ac.uk 

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What is the problem?

General population cancer screening in the UK is limited to selected cancers (cervical, breast, bowel and, for some high-risk individuals, lung). Most other cancers are detected after presentation of symptoms, when the disease tends to be at a more advanced stage and treatment options may be more limited. Blood-based multi-cancer early detection (MCED) tests aim to detect potential cancer signals (such as circulating cell-free deoxyribonucleic acid) from multiple cancers in the blood. 

The use of a MCED test as a screening tool in a healthy, asymptomatic population requires a high specificity and a reasonable sensitivity to detect early-stage disease so that the benefits of earlier diagnosis and treatment can be realised. A MCED test embedded within a national population-based screening programme, in addition to existing cancer screening programmes, may increase the number of cancers diagnosed at an earlier stage. However, identification of cancers with no effective treatments, even at an early stage, may offer no improvement in mortality or health-related quality of life (HRQoL). In addition, screening of healthy people for a wide range of cancers, and the expected lengthy time to diagnostic confirmation, may create anxiety and lead to unnecessary follow-up tests when false-positive test results occur.

Cancer screening is only available for some cancers. New tests that look for signs of cancer in blood (blood-based multi-cancer early detection tests) are being developed; they aim to detect multiple different cancers at an early stage, when they are potentially more treatable. The Galleri test is a blood-based MCED test which is currently being assessed by a trial in the NHS, and other MCED tests have become available privately in the UK and US.

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What are we doing? 

We previously published a review on the effectiveness of blood-based multi-cancer early detection tests for cancer screening, which included studies published between 2010 and 2023. We thoroughly searched for relevant studies and found over 8000 records. We included 30 completed studies and 6 ongoing studies of 13 different tests. 

As part of a wider programme of work involving a range of key stakeholders, we are now updating this review to look for additional studies published since 2023. We will identify and evaluate evidence from new studies of tests we found previously, as well as studies of new tests that have become available since the previous review. We will also include some additional outcomes of interest, such as cost-effectiveness and acceptability/satisfaction of clinical staff.