Tumor immune microenvironment of different lesions in patients with multiple primary lung cancer

e20549 Background: More and more multiple primary lung cancers (MPLCs) are found clinically. The driver genes and clinical differences between different lesions in MPLCs are obvious, which may affect the choice of subsequent treatment options. As a new type of therapy, immunotherapy has improved the survival of lung cancer patients to a certain extent. However, the efficacy of immunotherapy on different lesions of the same patient with MPLCs is not yet clear. Our study explored the similarities and differences of the tumor immune microenvironment in MPLCs lesions and provided a theoretical basis for immunotherapy in MPLCs. Methods: We collected 20 surgical tumor lesion samples from 10 patients with MPLCs for 289-gene panel RNA sequencing using NanoString nCounter. All tumor tumor immune microenvironment (TIME) cell infiltration scores were calculated as arithmetic mean of the constituent genes. Immune infiltration and expression of immune-related genes in different groups were assessed. Results: All 10 patients in our study were lung adenocarcinoma. Firstly, we classified them using an unsupervised consensus clustering based on TIME-signature gene expression used nonnegative matrix factorization of R package. The results revealed the cluster number of two was optimal (TIME Cluster1: n = 6 patients / 12 lesions; TIME Cluster2: n = 4 patients / 8 lesions). It is worth noting that the two lesions of the same patient are divided into the same group, indicating that the immune microenvironment status of the two lesions of the same person is basically similar. In addition, the nertrophils, NK CD56dim cells and GEP score of Cluster1 is significantly higher than that of Cluster2. Then we grouped them according to gender, ipsilateral or heteroside primary lesions, left or right lung, and pathological infiltration or non-infiltration, and found there was no significant difference in the immune microenvironment between the all the two groups. Conclusions: Dual primary samples from the same individual have similar immune microenvironments and may respond similarly to immunotherapy. Prospective immune-related clinical trials can be designed for further verification in MPLCs patients.