Researchers at Mass General Brigham announced on Mar. 18 that two new studies have found a connection between the health of the thymus in adults and increased longevity, as well as reduced risks for cardiovascular disease and cancer. The studies used artificial intelligence to analyze CT scans, revealing that adults with healthier thymuses lived longer and had lower chances of developing certain diseases.
The findings challenge the long-held belief that the thymus becomes irrelevant after childhood. This research suggests that the organ may play an important role in adult immune function and could become a target for personalizing disease prevention and cancer treatments.
"The thymus has been overlooked for decades and may be a missing piece in explaining why people age differently, and why cancer treatments fail in some patients," said Hugo Aerts, PhD, corresponding author on the papers and director of the Artificial Intelligence in Medicine (AIM) Program at Mass General Brigham. "Our findings suggest thymic health deserves much more attention and may open new avenues for understanding how to protect the immune system as we age."
The studies examined over 25,000 adults from a national lung cancer screening trial and more than 2,500 participants from the Framingham Heart Study. Researchers generated a "thymic health" score based on size, shape, and composition of the organ. Those with higher scores had about a 50% lower risk of death overall, a 63% lower risk of cardiovascular death, and a 36% lower risk of developing lung cancer compared to those with low scores. These results remained significant even after adjusting for age and other factors.
Lifestyle factors such as chronic inflammation, smoking, and high body weight were linked to poorer thymic health. In another study involving over 1,200 patients treated with immunotherapy for cancer, those with stronger thymic health had about a 37% lower risk of cancer progression and a 44% lower risk of death.
Researchers caution that these findings need further confirmation before being applied clinically. The imaging method is not yet ready for routine use in healthcare settings. The team is conducting additional research to see if other factors—such as unintended radiation exposure during lung cancer treatment—may affect thymic health.
"Improving our understanding and monitoring of thymic health could eventually help physicians better assess disease risk and guide treatment decisions," said Aerts.
