A: Precancerous lesions still have genetic and epigenetic changes much like cancers. So, similar signals look promising. The issue with developing liquid-biopsy-based tests to detect precancerous lesions is the scarcity of the cancer signal, i.e. biomarkers, in blood, which affects the sensitivity of an assay.

One approach is to identify some combination of biomarkers that could increase the sensitivity. There is work being done on this and, in addition to DNA, other biomarkers are being studied, like proteins and RNA.

Another approach is to use a different medium than blood, like bodily fluids that are closer to the source of the lesions desired to be detected. For example, the use of urine for detecting bladder lesions.

A: Although the primary endpoint had to do with reduction of Stage III–IV cancers, an in-depth analysis of the data is needed. Some of these data were presented at ASCO 2026.

What is important is to look at the type of tumors identified and at what stage. For some tumor types Stage III is manageable, while for other tumor types even Stage I is not.

Future randomized controlled prospective interventional studies should focus not only on the reduction of stage. For example, the endpoints should include a more detailed view that includes the cancer types detected, the stages identified, in how many cases there is an opportunity to treat people with intent to cure, and cancer-specific survival, to mention a few.

We need to know the benefits as well as the harms of MCED tests before widespread adoption.

A: I will start with what would make me pull back. That would be low specificity. This test is meant to be used as a screening test. Cancer in asymptomatic individuals is rare, approximately 1% depending on the age of the population. So, the test needs to be specific, avoiding a large number of false-positive results which could lead to unnecessary procedures.

What will keep me going is detection of cancers for which we do not have standard-of-care tests, detected before symptoms at stages where there is an opportunity to manage these individuals with intent to cure.

I see early detection of cancer as being proactive, instead of reactive, about detecting the disease to address underdiagnosis. Earlier detection of cancer will result in the reduction of sickness and death from cancer. It provides an opportunity to deliver management, including surgeries and therapies, with intent to cure and not just to prolong life. Drugs that are now used to treat metastatic stages of cancer should have better results in individuals whose cancer was detected earlier.

I do not mean to minimize other aspects associated with the successful clinical implementation of a test, like cost, accessibility, etc. I have focused my answer on why it is worth trying to deliver such a test.