Lung cancer is the most frequent cancer and the leading cause of cancer death all around the world. Anti-programmed cell death 1 (PD-1)/programmed cell death-ligand 1 (PD-L1) therapies have significantly improved the outcomes of non-small cell lung cancer (NSCLC) patients in recent years. However, the objective response rate in non-screened patients is only about 20%. It is very important to screen out the potential patients suitable for immunotherapy. Immunohistochemical staining of tumor tissue biopsies with PD-L1 antibodies can predict the therapeutic response to immunotherapy to some extent, but it still has some limitations. Recently some clinical studies have shown that PD-L1 expression in circulating tumor cells (CTC-PD-L1) is a potential independent biomarker and may provide important information for immunotherapy in NSCLC. This article will review technology for CTC-PD-L1 detection and the predictive value of CTC-PD-L1 for immunotherapy in NSCLC and review the latest clinical research progress.
With the broad application of high-resolution computed tomography (CT) and high rates of early lung cancer screening, the number of patients diagnosed with synchronous multiple primary lung cancer (sMPLC) has been increasing. It becomes of great prominence to distinct sMPLC from intrapulmonary metastases in clinical practice. An increasing number of studies have developed high-throughput sequencing based genetic approaches to specify the molecular characteristics of sMPLC, which contributes to a better understanding of its tumorigenesis. The genetic profile of sMPLC also benefits its diagnosis, which mainly relies on its clinicopathological criteria. Here, we summarize the progresses on the diagnostic criteria for sMPLC, and also molecular features of sMPLC from the perspective of clonality analysis.