Risk assessment of thyroiditis in patients undergoing chimeric antigen receptor T-cell therapy: A retrospective cohort analysis.

Abstract

e14523 Background: The introduction of immunotherapy in oncology has increased the risk of immune-immediate adverse effect. Chimeric antigen receptor T-cell (CART) therapy has revolutionized the treatment of hematological malignancies, raising concerns about its potential to cause immune-related adverse effects, such as CART-induced thyroiditis. However, evidence remains limited regarding the need for baseline or follow-up testing to detect thyroiditis in patients undergoing CART therapy. Methods: A retrospective cohort study was conducted using the National Inpatient Sample (NIS) database, the largest publicly available all-payer inpatient care database in the United States. We included patients aged 18-year-old who received CART therapy between 2018-2023, with no previous history of thyroid dysfunction. Two groups were compared: one group comprised patients with hematological malignancies (multiple myeloma, leukemia, and lymphoma) who received CART therapy and had no prior diagnosis of thyroiditis, and the other group consisted of patients with hematological malignancies with no history of CART therapy or myocarditis. The incidence of newly diagnosed thyroiditis following CART therapy was analyzed and compared between the groups. Results: After matching, 981 patients were included in each cohort. The incidence of newly diagnosed thyroiditis was 1.05% in both groups, with 10 patients affected in each cohort during the study period. There was no statistically significant difference in thyroiditis incidence between the CAR-T and control groups (p = 0.556). Kaplan-Meier analysis indicated no significant difference in time-to-event outcomes between the two cohorts (log-rank test, p = 0.556). The hazard ratio for thyroiditis onset in the CAR-T cohort compared to the control group was 1.702 (95% CI: 0.284–10.189), which was not statistically significant (p = 0.972). These findings suggest that CAR-T therapy does not increase the risk of developing thyroiditis. Conclusions: There was no significant difference in the incidence of thyroiditis between the CART-treated group and the non-CART-treated group (p > 0.05). These findings suggest that CART therapy does not significantly increase the risk of thyroiditis. Routine baseline or follow-up testing for thyroid disorders in patients undergoing CART therapy may not be necessary. This could help inform clinical guidelines, reduce unnecessary investigations, and optimize resource utilization. Further studies with larger patient cohorts are recommended to confirm these results.