Neoantigen load as a prognostic and predictive marker for stage II/III non‐small cell lung cancer in Chinese patients

BACKGROUND: The prognosis for patients with stage II/III non–small cell lung cancer (NSCLC) is unsatisfactory, even after complete tumor resection and adjuvant chemotherapy. Here, we assessed the prognostic and predictive value of immunogenomic signatures for stage II/III NSCLC in Chinese patients. METHODS: A total of 91 paired resected stage II/III NSCLC and normal tissues, including 47 squamous cell lung carcinomas (SCC) and 44 lung adenocarcinomas (ADC), were collected and analyzed using whole exome sequencing (WES) to identify immunogenomic signatures for association with clinicopathological variables and disease‐free survival (DFS). RESULTS: Higher neoantigen load (NAL, >2 neoantigens/Mb) exhibited better DFS for SCC patients (p = 0.021) but not ADC patients. A benefit from adjuvant chemotherapy was correlated with lower NAL (≤2 neoantigens/Mb) (p = 0.009). However, tumor mutation burden (TMB), mutations of individual gene, oncogene pathways, and antigen presentation machinery genes, and human leukocyte antigen (HLA)‐I number and HLA‐I loss of heterozygosity (LOH) had no prognostic or predictive value for DFS of SCC or ADC patients. CONCLUSIONS: NAL is a useful biomarker for lung SCC prognosis and prediction of chemotherapy responses in Chinese patients. The predictive value of NAL for adjuvant immunotherapy should be further explored in patients with resected NSCLC.