Abstract Background: Therapeutic options for advanced thyroid cancer (TC) remain limited once standard treatments fail. In our phase II trial (NCT 06146985), the multi-target kinase inhibitor famitinib combined with the PD-L1 antibody adebrelimab showed early antitumor activity. However, the immunologic basis of this synergy, particularly the contribution of tertiary lymphoid structures (TLSs), remains unclear. To determine whether TLS induction underlies treatment sensitivity, we integrated histopathology, single-cell transcriptomics, and patient-derived organoid (PDO) assays. Methods: TLS density and maturity were evaluated by H Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 2435.
Kou et al. (2026) studied this question.