Abstract 6110: Immune cell infiltrative characteristics reveals the superior efficacy of neoadjuvant immunochemotherapy versus chemotherapy alone in a real-world cohort of resectable non-small cell lung cancer

We aimed to analyze the efficacy of neoadjuvant immunochemotherapy versus chemotherapy alone in the real-world settings, and to further explore tumor immune microenviroment (TIME), as well as its influence on response of neoadjuvant therapy in patients with NSCLC. Fifty-three patients with neoadjuvant therapy (immunochemotherapy, n=22; chemotherapy alone, n=31), resectable stage I~III, age≥18 years, and ECOG performance status 0-1 were recruited in the study. Fluorescent multiplex immunohistochemistry was performed by the automated quantitative pathology imaging system with tumor samples obtained in radical surgery. The major pathologic response (MPR) rate was significantly higher in patients with neoadjuvant immunochemotherapy than chemotherapy alone (p=.025; OR=4.222, 95% CI: 1.292~13.800). Patients received immunochemotherapy had higher pathologic complete response (pCR) rate than those with chemotherapy (p=.168; OR=3.150, 95% CI: 0.792~12.535). Compared with chemo alone, the tumor to stroma ratio of CD68+CD163- density was significantly elevated in patients subjected to immunochemotherapy (p=.0399). When patients were stratified by the pathologic response to neoadjuvant immunochemotherapy, the CD56dim in stroma significantly increased in patients achieved pCR than non-pCR (p=.038). The density of CD3+CD4+ cells (stroma, p=.039; total, p=.027) and CD20+ (total, p=.027) immune cells was significantly higher in patients achieved MPR than non-MPR. In patients administered with neoadjuvant chemotherapy alone, the expression level of PD-1 (p=.036), the density of FoxP3+ (stroma, p=.025; total, p=.013) and CD3+CD4+FoxP3+ (total, p=.042) cells significantly reduced in patients reached pCR. The density of CD20+ cells in stroma (p=.034) and the number of tertiary lymphoid structures (TLS; p=.006) were significantly higher in patients reached MPR. In conclusion, the therapeutic efficacy was improved by neoadjuvant immunochemotherapy in patients with NSCLC, which may be associated with the TIME remodeling, especially the migration of M1 macrophage from stroma to tumor islet. Clusters of NK, Th, Treg and B, PD-1, and TLS also play important role in response to neoadjuvant therapy. This work was supported by National Natural Science Foundation of China (NO. 62076254) Citation Format: Wenhan Cai, Miao Jing, Jiaxin Wen, Yajun Gu, Xiaochen Zhao, Zhiqiang Xue. Immune cell infiltrative characteristics reveals the superior efficacy of neoadjuvant immunochemotherapy versus chemotherapy alone in a real-world cohort of resectable non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6110.