Background: Lung Cancer Screening (LCS) is an evolving field with variations in its implementation in various countries. There are only scarce data from National LCS programs. Aim: We aim to provide an up-to-date overview of the current evidence regarding the use of biomarkers in LCS. Materials and Methods: A multidisciplinary Task Force experts’ panel collaborated and conducted a systematic literature search, followed by screening, review and synthesis of available evidence. Results: Biomarkers in LCS could be used to improve risk stratification in high-risk participants, improve clarification regarding indeterminate lung nodules and avoid overdiagnosis in suspicious lung findings. Currently, there seem to be promising biomarkers (blood/serum/breath) that have been studied in various trials; however, there is still a lack of solid evidence in clinical validation that would pave the way for their integration into LCS programs. Conclusions: Biomarkers are the next logical step in improving the LCS pathway and its efficiency by playing an adjuvant role in a minimally invasive way. National LCS programs and pilot studies should integrate biomarkers to validate their accuracy in real-life LCS participants.

Background: Previous preclinical data have shown that the dynamic cross-talk between abnormal tumor vasculature and immune cell factors in the tumor microenvironment may exert a critical role in the progression and treatment resistance of non-small cell lung cancer (NSCLC). In the clinical setting, a variety of blood-based angiogenesis- and immune-related factors are being increasingly investigated as potential biomarkers of prognosis or treatment response in immunotherapy-treated NSCLC. We herein aimed to evaluate the clinical relevance of the peripheral blood levels of vascular endothelial growth factor-A and -B (VEGF-A and VEGF-B, respectively), soluble programmed cell death-1 (sPD-1), and programmed cell death-ligand 1 (sPD-L1) in patients with advanced NSCLC treated with immune checkpoint inhibitors (ICIs). Methods: Consecutive patients with advanced-stage, non-oncogene-addicted NSCLC, eligible to receive ICIs at the Oncology Unit of Sotiria Athens General Hospital, were prospectively recruited. A group of sex- and age-matched healthy controls was also enrolled for the evaluation of the potential diagnostic significance of the examined biomarkers. Serum levels of all biomarkers were measured using ELISA, both before and after treatment, and were correlated with standard clinicopathological features of patients, treatment response, progression-free survival (PFS), and overall survival (OS). Results: A total of 55 patients and 16 healthy controls were included in the final analysis. The mean age of patients and controls was 66.5 years (SD = 8.0 years) and 65.4 years (SD = 9.1 years), respectively. The majority of patients (65.5%) received pembrolizumab in combination with chemotherapy, while the remaining patients received pembrolizumab monotherapy. ROC curve analysis showed that VEGFB and sPD-1 were the only markers with a significant diagnostic value. Higher pre-treatment values of sPD-L1 (HR = 1.68; p = 0.040) and sPD-1 (HR = 10.96; p = 0.037) as well as higher post-treatment values of VEGF-B (HR = 2.99; p = 0.049) were all significantly associated with a reduced OS in univariate Cox regression analysis. The adverse prognostic significance of higher pre-treatment values of sPD-L1 (HR = 2.10; p = 0.014) and higher post-treatment values of VEGFB (HR = 3.37; p = 0.032) was further confirmed in multivariate analysis. Conclusions: Our study results suggest that serum levels of sPD-L1 and VEGF-B may independently predict prognosis in ICI-treated advanced-stage NSCLC.

Background: Soluble immune checkpoint molecules, including soluble PD-1 (sPD-1) and soluble PD-L1 (sPD-L1), have emerged as potential minimally invasive biomarkers in non-small cell lung cancer (NSCLC). However, their diagnostic, kinetic, and prognostic significance across different disease settings remains unclear. This prospective study evaluated baseline levels, longitudinal fluctuations, and clinical associations of sPD-1 and sPD-L1 in early- and advanced-stage NSCLC. Methods: Three cohorts were prospectively enrolled: early-stage NSCLC patients undergoing curative surgery (n = 25), advanced-stage NSCLC patients receiving pembrolizumab-based immunotherapy (n = 55), and non-oncological controls (n = 16). Serum sPD-1 and sPD-L1 were measured by ELISA at baseline and at four months post-surgery (early stage) or six months post-treatment (advanced stage). Baseline comparisons, longitudinal changes, correlation with tumor PD-L1 expression (TPS), and associations with recurrence (early stage) or 6-month objective response (advanced stage) were assessed. Results: Baseline sPD-1 and sPD-L1 levels did not differ significantly among controls, early-stage, and advanced-stage cohorts. In early-stage patients, sPD-L1 increased post-operatively (p = 0.006) while sPD-1 decreased (p < 0.001). In advanced-stage disease, sPD-1 declined during immunotherapy (p < 0.001), whereas sPD-L1 remained unchanged (p = 0.37). Baseline levels and continuous percent changes were not predictive of most outcomes. However, a ≥20% postoperative increase in sPD-L1 was strongly associated with recurrence in early-stage NSCLC (OR = 10.29; 95% CI: 1.40–215.20; p = 0.019). No sPD-1/PD-L1 metric predicted response in advanced disease. Baseline sPD-L1 showed no correlation with tumor PD-L1 expression (ρ = −0.09, p = 0.53) in the advanced-stage cohort. Conclusions: sPD-1 and sPD-L1 demonstrate distinct kinetic patterns across NSCLC settings. A postoperative >20% surge in sPD-L1 may identify early-stage patients at elevated risk of recurrence, whereas soluble checkpoints were not predictive of treatment response in advanced disease. These findings support further investigation of soluble checkpoint dynamics as complementary biomarkers in NSCLC management in larger cohorts.

Background/Objectives: Total cell-free DNA (cfDNA) is not tumour-specific and may be affected by peri-operative injury and inflammation. We evaluated peri-operative plasma cfDNA dynamics and explored associations with recurrence and mortality in resectable non-small cell lung cancer (NSCLC). Methods: This prospective pilot cohort included 35 patients undergoing lobectomy with systematic nodal dissection and 30 healthy controls. Samples were collected pre-operatively, from the tumour-draining pulmonary vein before major manipulation, peripherally after resection, and on postoperative day 14. Analyses included group comparisons, receiver operating characteristic analysis, logistic regression and Cox regression. Results: Pre-operative cfDNA was higher in patients than controls (mean 1.96 versus 1.08 ng/µL; p = 0.002). Discrimination was modest (AUC 0.67, 95% CI 0.54–0.80), with sensitivity 49% and specificity 93% at an internally selected cut-off. cfDNA differed across timepoints (overall p = 0.008), with higher intra-operative and post-resection values than pre-operative values. Among 34 patients with complete three-year outcomes, 12 recurred and 13 died. Pre-operative cfDNA was associated with recurrence in multivariable logistic regression (adjusted OR 2.47, 95% CI 1.07–5.67; p = 0.034). Day-14 cfDNA was higher among patients who died (5.35 versus 2.17 ng/µL; p = 0.008). Conclusions: Total cfDNA showed modest diagnostic discrimination and exploratory outcome associations. Small sample size, potential model overfitting and incomplete analytical documentation limit interpretation. These hypothesis-generating findings require independent validation with standardised methods, peri-operative covariates and tumour-informed circulating tumour DNA assays.