Early detection of cancer
A new blood test that may detect more than 50 types of cancer will be piloted by the NHS in 2021. The test checks for molecular changes that can identify many types of cancer currently difficult to detect at an early stage. These include cancers of the head and neck, ovaries, pancreas and oesophagus, plus some haematological cancers.
The Galleri test has been developed by the healthcare company GRAIL Inc, based in California, whose stated mission is to detect cancer early. An earlier version of Galleri detected over 50 types of cancer with a low false positive rate of less than 1% through a single blood draw. Modelling data show that adding Galleri to existing care has the potential to decrease the number of cancers diagnosed at late stage by nearly half, which could reduce the total number of cancer deaths in the UK by approximately one-fifth. According to the NHS, in England, around half of cancers are currently diagnosed at stage one or two, but the NHS Long Term Plan is aiming to increase that to three quarters by 2028. Patients whose condition is diagnosed at stage one typically have between five and 10 times the chance of surviving compared with those found at stage four.
The immediate plan is for 25,000 people with possible cancer symptoms to be offered testing to speed up their diagnosis after being referred to hospital in the normal way. The trial will also include 140,000 participants aged 50 to 79 who have no symptoms but will have annual blood tests for three years. If the NHS programme shows the test also works as expected for people without symptoms, it will be rolled out to become routinely available. Results of these studies would be expected by 2023, and if outcomes are positive, then they would be expanded to involve around one million participants across 2024 and 2025.