A new study, supporting the accuracy of multi-cancer early detection (MCED), could have significant implications for the future of cancer screening, care, and provision.
According to European Society for Medical Oncology (ESMO) 2022 Scientific Co-Chair Fabrice André, cancer doctors, care providers and payers need to prepare for a major shift in cancer screening that will affect almost every stage of cancer diagnosis and treatment.
“It is a duty of professional societies like ESMO to raise awareness of the fact that within the next five years, we will need more doctors, surgeons and nurses, together with more diagnostic and treatment infrastructure, to care for the rising number of people who will be identified by multi-cancer early detection tests,” explained André.
“We need to involve all stakeholders in deciding new pathways of care. We need to agree who will be tested and when and where tests will be carried out, and to anticipate the changes that will happen as a result of these tests, for example in the diagnosis and treatment of people with pancreatic and other cancers that are usually diagnosed at a much later stage.”
MCED tests are highly effective
MCED cancer screening tests, which are currently in development, can detect common cancer signals from over 50 different types of cancer. MCED tests can also predict where in the body the signal has come from.
Cancer signals arise in the body from small sequences of circulating tumour DNA (ctDNA) in the blood. These signals have different methylation patterns from non-tumour DNA.
In the study presented at the ESMO Congress 2022, the MCED test detected cancer signals in 1.4% of the 6,621 participants. Each participant was aged 50 and over and was not known to have cancer. After the cancer screening, 38% of those with a positive MCED test were confirmed to have cancer.
Of the 6,290 people who received a negative MCED test, 99.1% were confirmed to be cancer free. The average time for those with a positive test result to find out whether they had cancer or decide there is no evidence of malignancy was 79 days. 73% of those with a positive cancer screening test received confirmation within three months.
MCED cancer screening is safer and more efficient
“The results are an important first step for early cancer screening detection tests because they showed a good detection rate for people who had cancer and an excellent specificity rate for those who did not have cancer. In people with a positive test, it took less than two months to confirm the diagnosis if they had cancer and it took a bit longer if they did not have cancer,” explained study senior author Deb Schrag, of the Memorial Sloan Kettering Cancer Center, New York.
“An important finding was that few participants with a false positive screening test required multiple invasive procedures such as endoscopies and biopsies. This finding should help to allay concerns that these tests could cause harm by generating unnecessary procedures in people who are well,” added Schrag.
Schrag stressed the importance of continued standard cancer screening for tumours, such as colorectal and breast cancer. MCED tests are currently being refined and validated for cancers where there are no screening options, such as pancreatic, small bowel and stomach cancer.
“This study indicates that hope is on the horizon for detecting cancers that are currently unscreenable, but of course, much more work is needed and, with experience and larger samples, these assays will improve. The tests need to be refined so they are better at distinguishing tumour DNA from all the other DNA that is circulating in the blood. It is also critical to note that the purpose of cancer screening is not to decrease the incidence of cancer, but rather to decrease cancer mortality” said Shrag.
This study is the first prospective investigation to show that an MCED test can detect cancer in undiagnosed patients. Previous studies have only tested patients who were known to have cancer.
Several further studies are now underway, including a major randomised trial involving 140,000 asymptomatic people in England. This research will investigate the clinical effectiveness of MCED testing on cancer outcomes.