Purpose: We assessed whether perioperative circulating tumor DNA (ctDNA) could be a biomarker for early detection of molecular residual disease (MRD) and prediction of postoperative relapse in resected non–small cell lung cancer (NSCLC). Experimental Design: Based on our prospective, multicenter cohort on dynamic monitoring of ctDNA in lung cancer surgery patients (LUNGCA), we enrolled 950 plasma samples obtained at three perioperative time points (before surgery, 3 days and 1 month after surgery) of 330 stage I–III NSCLC patients (LUNGCA-1), as a part of the LUNGCA cohort. Using a customized 769-gene panel, somatic mutations in tumor tissues and plasma samples were identified with next-generation sequencing and utilized for ctDNA-based MRD analysis. Results: Preoperative ctDNA positivity was associated with lower recurrence-free survival (RFS; HR = 4.2; P < 0.001). The presence of MRD (ctDNA positivity at postoperative 3 days and/or 1 month) was a strong predictor for disease relapse (HR = 11.1; P < 0.001). ctDNA-based MRD had a higher relative contribution to RFS prediction than all clinicopathologic variables such as the TNM stage. Furthermore, MRD-positive patients who received adjuvant therapies had improved RFS over those not receiving adjuvant therapy (HR = 0.3; P = 0.008), whereas MRD-negative patients receiving adjuvant therapies had lower RFS than their counterparts without adjuvant therapy (HR = 3.1; P < 0.001). After adjusting for clinicopathologic variables, whether receiving adjuvant therapies remained an independent factor for RFS in the MRD-positive population (P = 0.002) but not in the MRD-negative population (P = 0.283). Conclusions: Perioperative ctDNA analysis is effective in early detection of MRD and relapse risk stratification of NSCLC, and hence could benefit NSCLC patient management.

Tumor-associated macrophages (TAMs) are important components of cancer microenvironment. In the present study, we searched PubMed, Embase, Cochrane library and Web of Science to perform a meta-analysis of 20 studies including a total of 2,572 non-small cell lung cancer (NSCLC) patients, in order to determine the association between TAMs and NSCLC prognosis. The combined hazard ratio (HR) of 9 studies showed that the density of total CD68+ TAMs in the tumor islet and stroma was not associated with overall survival (OS) of the patients. However, the pooled HR of 4 studies showed that high density of CD68+ TAMs in the tumor islet predicted better OS, while the pooled HR of 6 studies showed that high density of CD68+ TAMs in the tumor stroma was associated with poor OS. A high islet/stroma ratio of CD68+ TAMs was associated with better OS. A high density of M1 TAMs in the tumor islet was associated with better OS, while a high density of M2 TAMs in the tumor stroma predicted poor OS. These findings suggest that, although the density of total CD68+ TAMs is not associated with OS, the localization and M1/M2 polarization of TAMs are potential prognostic predictors of NSCLC.

BackgroundTumor microenvironment is composed of tumor cells, fibroblasts, endothelial cells, and infiltrating immune cells. Tumor-associated immune cells may inhibit or promote tumor growth and progression. This study was conducted to determine whether the number and microlocalization of macrophages, mature dendritic cells and cytotoxic T cells in non-small cell lung cancer are associated with patient's survival time.MethodsNinety-nine patients with non-small cell lung cancer (NSCLC) were included in this retrospective study. Paraffin-embedded NSCLC specimens and their clinicopathological data including up to 8-year follow-up information were used. Immunohistochemical staining for CD68 (marker for macrophages), CD83 (marker for mature dendritic cells), and CD8 (marker for cytotoxic T cells) was performed and evaluated in a blinded fashion. The numbers of immune cells in tumor islets and stroma, tumor islets, or tumor stroma were counted under a microscope. Correlation of the cell numbers and patient's survival time was analyzed using the Statistical Package for the Social Sciences (version 13.0).ResultsThe numbers of macrophages, mature dendritic cells and cytotoxic T cells were significantly more in the tumor stroma than in the tumor islets. The number of macrophages in the tumor islets was positively associated with patient's survival time, whereas the number of macrophages in the tumor stroma was negatively associated with patient's survival time in both univariate and multivariate analyses. The number of mature dendritic cells in the tumor islets and stroma, tumor islets only, or tumor stroma only was positively associated with patient's survival time in a univariate analysis but not in a multivariate analysis. The number of cytotoxic T cells in the tumor islets and stroma was positively associated with patient's survival time in a univariate analysis but not in a multivariate analysis. The number of cytotoxic T cells in the tumor islets only or stroma only was not associated with patient's survival time.ConclusionsThe number of macrophages in the tumor islets or stroma is an independent predictor of survival time in NSCLC patients. Counting macrophages in the tumor islets or stroma is more useful in predicting patient's survival time than counting mature dendritic cells or cytotoxic T cells.

IMPORTANCEIt is important to develop a surgical technique to reduce dissemination of tumor cells into the blood during surgery.OBJECTIVE To compare the outcomes of different sequences of vessel ligation during surgery on the dissemination of tumor cells and survival in patients with non-small cell lung cancer. DESIGN, SETTING, AND PARTICIPANTSThis multicenter, randomized clinical trial was conducted from December 2016 to March 2018 with patients with non-small cell lung cancer who received thoracoscopic lobectomy in West China Hospital, Daping Hospital, and Sichuan Cancer Hospital. To further compare survival outcomes of the 2 procedures, we reviewed the Western China Lung Cancer database (2005-2017) using the same inclusion criteria.INTERVENTIONS Vein-first procedure vs artery-first procedure. MAIN OUTCOMES AND MEASURESChanges in folate receptor-positive circulating tumor cells (FR + CTCs) after surgery and 5-year overall, disease-free, and lung cancer-specific survival.RESULTS A total of 86 individuals were randomized; 22 patients (25.6%) were younger and 64 (74.4%) older than 60 years. Of these, 78 patients were analyzed. After surgery, an incremental change in FR + CTCs was observed in 26 of 40 patients (65.0%) in the artery-first group and 12 of 38 (31.6%) in the vein-first group (P = .003) (median change, 0.73 [interquartile range (IQR), −0.86 to 1.58] FU per 3 mL vs −0.50 [IQR, −2.53 to 0.79] FU per 3 mL; P = .006). Multivariate analysis confirmed that the artery-first procedure was a risk factor for FR + CTC increase during surgery (hazard ratio [HR], 4.03 [95% CI,]; P = .005). The propensity-matched analysis included 420 patients (210 with vein-first procedures and 210 with artery-first procedures). The vein-first group had significantly better outcomes than the artery-first group for 5-year overall survival (73.6% [95% CI, 64.4%-82.8%] vs 57.6% [95% CI, 48.4%-66.8%]; P = .002), disease-free survival (63.6% [95% CI, 55.4%-73.8%] vs 48.4% [95% CI, 40.0%-56.8%]; P = .001), and lung cancer-specific survival (76.4% [95% CI, 67.6%-85.2%] vs 59.9% [95% CI, 50.5%-69.3%]; P = .002). Multivariate analyses revealed that the artery-first procedure was a prognostic factor of poorer 5-year overall survival (HR, 1.65 [95% CI, 1.07-2.56]; P = .03), disease-free survival (HR, 1.43 [95% CI, 1.01-2.04]; P = .05) and lung cancer-specific survival (HR = 1.65 [95% CI, 1.04-2.61]; P = .03). CONCLUSIONS AND RELEVANCELigating effluent veins first during surgery may reduce tumor cell dissemination and improve survival outcomes in patients with non-small cell lung cancer.TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT03436329