The Tumor Microenvironment and Clinical Implications of Radiotherapy and Immunotherapy for Liver Metastases from Non-Small Cell Lung Cancer (NSCLC)

Abstract

Immunotherapy emergence has triggered a profound change in the approach to treating advanced non-small cell lung cancer (NSCLC). However, challenges arise when tumors metastasize to critical sites such as the brain, bones, and liver, impeding the efficacy of immunotherapeutic interventions. Particularly, liver metastases exhibit a considerably unfavorable prognosis in comparison to other metastatic sites, owing in part to the prevailing immunosuppressive microenvironment within the liver that hampers immune-based therapies. Hence, it is imperative to investigate novel strategies that can bolster immune responses and prolong the survival of individuals with liver metastases (LM). Radiotherapy (RT) stands out as a primary modality in cancer treatment. Preclinical studies have revealed its capability to reshape the tumor microenvironment (TME), shifting it from an immunosuppressive setting to one that promotes immune activity. This transformative mechanism holds the promise of amplifying the effectiveness of immune-based treatments. This article will discuss the mechanisms by which radiotherapy improves the immunosuppressive microenvironment in the liver, provide a comprehensive review of the research progress on the combined application of RT and immunotherapy for LM, and offer insights into the establishment of novel therapeutic strategies for patients with LM.