Dr. Achim Regenauer shares an overview of this important study’s findings and his perspective on the impact on cancer detection and Life & Health insurance.
In an article published last week in the leading cancer journal, Annals of Oncology, researchers reported the following encouraging results of an independent validation study of the Galleri test, a liquid biopsy test for multiple cancers. This test is one of several Multi-Cancer Early Detection (MCED) tests being developed in a fast emerging and highly competitive field that will have soon a significant impact on detecting cancer at an earlier stage.
The results of the case-control study (i.e. not yet reflective of performance within a screening population) were that the test accurately detected multiple cancers in a simple blood test, often before any symptoms, and that it also predicted the location of the cancers with a high degree of accuracy.
If further corroborations from larger population studies follow – already underway in the US and UK with results expected within the next few years – this first study result brings us a step closer to the large-scale application of early, multi-cancer testing from a blood test.
Currently, only five useful cancer (traditional) early detection screening tests are available: for breast, colorectal, cervical, lung and prostate cancer. In the US, for example, these cancers represent up to 42% of annual cancer incidence in people aged 50-79 years, leaving many other cancers, such as oesophageal, liver and pancreatic cancers, without screening options (representing approximately 71% of cancer deaths). Of cancers without early detection screening options, several (e.g. lung, ovarian and pancreatic cancer) also present late, meaning late detection and late treatment starts, and therefore poor patient outlooks.
In addition, although traditional screening tests contribute significantly to a reduction of cancer-specific mortality, they are also associated with high false-positive rates, overdiagnosis and overtreatment.
The Galleri test, developed by GRAIL, is a liquid biopsy test that uses next-generation genome sequencing to analyse the arrangement of methyl groups (indicating the presence of cancer) on circulating cell-free DNA (abnormal DNA that has been shed from cells) from a blood sample.
This innovative test is reported to detect more than 50 types of cancer from a single blood draw, 45 of which currently have no other screening option.
The Galleri test is one of three multi-cancer screening tests under investigation – the other two being the CancerSEEK assay and the PanSeer assay.
The test is available on prescription in the US (cost approximately USD 950, results within two weeks). FDA approval is expected to be sought in 2023. A pilot trial is being run by the UK’s National Health Service, with a broader access expected in 2024/25.
The “Circulating Cell-free Genome Atlas Study” (CCGA Study) is the first validation trial of the Galleri test. This prospective, case-controlled study with a 5-year longitudinal follow-up, recruited individuals of over 20 years of age, looked at more than 50 distinctive cancer types in blood and tumor tissue samples from 15,254 people from 142 locations in North America, including people with new cancer and blood samples from people without a cancer diagnosis. Subsequently, the test entered into a further three larger clinical development trials to examine its feasibility for screening populations: STRIVE (US), SUMMIT (UK, 140,000 participants, first results expected by 2023) and PATHFINDER (US) studies.
Last week’s published findings – the topic of this article – are the first clinical validation of a sub-study of the CCGA Study investigating the performance of the Galleri test in 2,823 people already diagnosed with cancer and 1,254 people without cancer. The mean age of all participants was 60.6 years (55.4% female). Specificity, sensitivity and prediction accuracy were measured.
Specificity: 99.5% (very high). A positive test result is correct (cancer exists) 99.5% of the time (only 1 in 200 positive results are false). High specificity (>99%) is very important for cancer as false positives cause considerable harm.
Sensitivity (the likelihood of detecting a cancer that exists): 51.5% (fairly low). However, results were dependent on the cancer stage (stage 1: 16.8%; stage 2: 40.4%; stage 3: 77.0%; stage 4: 90.1%) and type; there was higher sensitivity in the prespecified group of 12 cancer classes that account for two thirds of annual cancer deaths in the US (anal, bladder, bowel, oesophageal, stomach, head and neck, liver and bile duct, lung, ovarian, pancreatic cancers, lymphoma and multiple myeloma). For these cancers, the overall sensitivity was 76.3% for all stages and 67.6% for stages 1-3.
The Galleri test therefore detects approximately 5 in 10 cancers. Although this is low, it must be stressed that for most cancers there is no other available screening option, so if used alongside existing screening tests, overall detection is substantially increased.
With these encouraging results, the Galleri test can be considered the tip of the iceberg in terms of how genetics will revolutionize oncology within the next decade.
Healthcare systems, Health insurance and Life insurance (Critical Illness policies) may in the medium-term be confronted with:
Our experts are in full swing working on solutions for insurers to adapt their products to stay relevant and sustainable over coming years. Do get in touch with me if you’d like to discuss this topic or to talk to one of our regional experts about solutions for the new cancer detection reality.
Dr. Achim Regenauer, Chief Medical Officer, Life & Health
 According to GRAIL, the developers of the Galleri test.