Abstract:
Objective To study the effect of tertiary lymphoid structures (TLS) on the pathological response and prognosis of patients with non-small cell lung cancer (NSCLC) receiving neoadjuvant therapy.
Methods We retrospectively collected the data of 132 patients with NSCLC who underwent neoadjuvant therapy and surgery at Tianjin Chest Hospital between January 2019 and December 2023, including 40 in the neoadjuvant chemotherapy (NC) group and 92 in the NC plus immunotherapy (NCI) group. The percentage of residual viable tumor (RVT) and tumor infiltrating lymphocyte (TIL) counts were evaluated by hematoxylin and eosin (H&E) staining, while TLS number and maturity were assessed by H&E and immunohistochemical staining. The differences in TLS number and maturity and effects on patient pathological response and prognosis were compared between groups.
Results TIL count, total TLS number, pathological complete response and major pathological response rates were significantly higher in the NCI versus NC group (P<0.001). Moreover, a multivariate Logistic analysis showed that TLS number and maturity and TIL count affected pathological response in the NCI group (P<0.05). A multiple linear regression analysis indicated that a low TIL count was a risk factor for a high RVT in the NC group, while a low number of mature TLS, low TIL count, and N stage were independent risk factors for a high RVT in the NCI group (all P<0.05). In the NCI group, a multivariate Cox regression analysis showed that a low number of mature TLS (P=0.001) and low TIL count (P=0.009) were independent predictors of disease-free survival (DFS), while a survival analysis showed that patients in the NCI group with high (vs. low) numbers of mature TLS and a high (vs. low) TIL count had significantly longer DFS (all P<0.001).
Conclusions A low number of mature TLS and low TIL count were associated with an adverse pathological response and short DFS in patients with NSCLC. Thus, TLS maturity and TIL count can predict the pathological response and prognosis of patients with NSCLC treated with NCI.