How the immune system signals early cancer
The study, published in Nature Communications, focuses on the body’s own defense mechanism: T cells. In Lynch Syndrome, mutations cause “microsatellite instability,” which leads to the creation of tumor-specific neoantigens—essentially protein fragments on the surface of cancer cells that the immune system recognizes as foreign. Led by Eduardo Vilar-Sanchez, M.D., Ph.D., the research team sequenced T cell receptors (TCRs), the specialized “locks” that T cells utilize to identify and attack these neoantigens. By analyzing blood samples (peripheral blood mononuclear cells) from 277 individuals—including survivors, cancer-free carriers (previvors), and a control group—the team found that the immune system often begins responding to early signs of cancer long before a tumor is visible on a scan or during a physical exam. Crucially, the researchers matched these blood samples with colorectal tissues from cancers and pre-cancers. They discovered that up to 41% of the expanded TCRs found in pre-cancerous tissues were likewise detectable in the blood of Lynch Syndrome carriers, but not in those without the syndrome. This suggests the blood carries a traceable signature of the immune system’s attempt to fight early malignancy.Moving toward personalized surveillance
Common Questions About the Study
- Is this a replacement for colonoscopies? No. This is intended as a tool for risk assessment and stratification to aid clinicians decide when and how to screen, not as a replacement for the gold-standard visual examination of the colon.
- Who can gain this test? Currently, this is a research discovery. We see not yet available as a commercial or clinical diagnostic test.
- Does this test diagnose cancer? The biomarker identifies “immune signatures” associated with cancer risk and early response. it is designed to characterize susceptibility and monitor activity rather than serve as a standalone diagnostic for a tumor.



