MCED Tests Mark New Era of Early Cancer Detection

Researchers have presented new data supporting the accuracy of multi-cancer early detection (MCED) blood testing that could have major implications for future cancer care provision. New MCED tests in development can detect a common cancer signal from over 50 different types of cancer and predict where the signal has come from in the body. The signal arises from small sequences of circulating tumor DNA (ctDNA) in the blood which have some different methylation patterns from non-tumor DNA.

In the PATHFINDER study presented at the ESMO Congress 2022, organized by the European Society for Medical Oncology (ESMO, Lugano, Switzerland), an MCED test detected a cancer signal in 1.4% of 6621 people aged 50 years and over who were not known to have cancer, and cancer was confirmed in 38% of those with a positive test. Of 6290 people who were cancer free, 99.1% received a negative test result. Among those with a positive test result, the time to achieve diagnostic resolution (i.e. to find cancer or decide there was no evidence of malignancy requiring further investigation) was a median of 79 days. Among participants with a positive screening test, diagnostic resolution was achieved within three months for 73%.

The study reported at the ESMO Congress 2022 is the first prospective investigation to show that an MCED test can detect cancer in patients with undiagnosed cancer, as previous studies used tests only in patients already known to have cancer. A number of further studies are now underway including a major randomized clinical trial enrolling 140,000 asymptomatic people in England to investigate the clinical effectiveness of MCED testing on cancer outcomes. However, the researchers have stressed the importance of continued standard screening for tumors, such as breast and colorectal cancer, while MCED tests are being refined and validated for cancers such as pancreatic, small bowel and stomach cancer where there are currently no screening options.

“The results are an important first step for early cancer 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 primarily because physicians opted to perform imaging studies and then repeat them a second time several months later to investigate the possibility of a cancer diagnosis,” explained study senior author Deb Schrag, Memorial Sloan Kettering Cancer Center.

“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.

Related Links:
ESMO