Mature tertiary lymphoid structures predict immune checkpoint inhibitor efficacy in solid tumors independently of PD-L1 expression

Only a minority of patients derive long-term clinical benefit from anti-programmed cell death protein 1 (anti-PD-1) or anti-programmed death-ligand 1 (anti-PD-L1) monoclonal antibodies. The presence of tertiary lymphoid structures (TLSs) has been associated with improved survival in several tumor types. Here, using a large-scale retrospective analysis of three independent cohorts of patients with cancer who were treated with anti-PD-1 or anti-PD-L1 antibodies, we show that the presence of mature TLSs was associated with improved objective response rates, progression-free survival and overall survival, independent of PD-L1 expression status and CD8⁺ T cell density. These results pave the way for using TLS detection to select patients who are more likely to benefit from immune checkpoint blockade.