Overview
- Two Nature papers from Mass General Brigham applied machine learning to routine chest CT scans to quantify thymic structure across a national lung screening cohort of roughly 25,000–27,000 adults and more than 2,500 participants in the Framingham Heart Study.
- Higher thymic health scores correlated with about a 50% lower risk of death, a 63% lower risk of cardiovascular death, and a 36% lower risk of developing lung cancer after adjustment for age and other factors.
- In over 1,200 cancer patients receiving immune checkpoint therapy, stronger thymic health was associated with a 37% lower risk of disease progression and a 44% lower risk of death independent of patient, tumor, and treatment variables.
- Poorer thymic condition tracked with chronic inflammation, smoking, and higher body weight, and the analyses revealed large person-to-person variability in how the thymus ages.
- The authors emphasize the results show associations rather than causation, the imaging metric is not ready for clinical use, and prospective studies are underway including an assessment of unintended radiation exposure to the thymus.