NSCLC Stage IV Without EGFR/ALK Mutation

This study includes patients with advanced non-small cell lung cancer (NSCLC) - either unresectable stage III or stage IV adenocarcinoma without actionable driver mutations - who are treated with pembrolizumab in combination with platinum-based doublet chemotherapy, irrespective of PD-L1 expression levels. The primary objective is to assess treatment response through integration of serial T-cell receptor (TCR) repertoire sequencing (Rep-seq), capturing longitudinal changes in T-cell clonality and diversity. These immune dynamics will be correlated with radiographic response assessed by RECIST 1.1, with the aim of improving the accuracy of response classification, including differentiation between progression, pseudo-progression, and hyperprogression. Additionally, circulating tumor DNA (ctDNA) levels will be measured longitudinally (pre-treatment and during treatment) to evaluate their potential as a complementary biomarker of disease burden and treatment efficacy in the context of chemo-immunotherapy.

It is planned to carry out a multicenter umbrella study to find the optimal organ combination and the best radioimmunotherapy combination pattern, so as to improve the survival of NSCLC patients with multiple metastases. At the same time, by using multimodal omics data, machine learning will be employed to construct a prediction model for the abscopal effect, and explore the immunoregulation of organ-specific radiotherapy and biomarkers of the abscopal effect. The main objective is to find the optimal organ combination and the best radioimmunotherapy combination pattern.

This study aims to conduct a prospective, multicenter, umbrella clinical study to compare the abscopal effects of different radiotherapy fractionation patterns combined with Benmelstobart, and to explore an efficient and low-toxic treatment strategy for non-small cell lung cancer (NSCLC) with multiple metastases. The main objective is to explore and compare the control rates of abscopal lesions in NSCLC patients with multiple metastases when different radiotherapy fractionation patterns are combined with Benmelstobart.