Thymectomy Linked to Cancer, Mortality

Researchers asked whether removing the thymus in adults during chest surgery is linked to later cancer, death, and immune-cell production. In matched surgical cohorts, five-year mortality was 8.1% after thymus removal versus 2.8% in controls; cancer occurred in 7.4% versus 3.7%. More than a decade later, blood samples also carried a quieter signal. Patients who had undergone removal had lower signal-joint T-cell receptor excision circles, or sjTRECs: DNA traces made when the thymus produces new T cells, the immune cells that help recognize threats. This shows that adult thymic output persisted in the control group. The study found associations, not proof that removal caused cancer or death, but it supports preserving the adult thymus when surgery allows.