Large multi‑cohort analyses and AI‑enabled CT studies linked adult thymic status to cancer immunotherapy outcomes and long‑term mortality risk. A Nature study and supporting real‑world analyses showed that measures of thymic integrity correlate with response to immune checkpoint blockade across tumor types and with all‑cause and cancer‑specific outcomes in general populations. Investigators used imaging, clinical records and outcomes datasets—some leveraging AI segmentation of thousands of CT scans—to quantify thymic involution and associate it with immune competence measures. Patients with preserved thymic tissue exhibited higher T‑cell diversity and better responses to immunotherapy. These findings position thymic assessment as a potential stratification biomarker for immuno‑oncology trials and raise the prospect of thymic‑targeted interventions or patient selection strategies. Operationalizing thymus metrics for clinical decisions will require standardized imaging protocols and prospective validation.