Rationale: Myeloid-derived suppressor cell (MDSC) expansion has been found to play a role in disease progression in patients with cancer. However, the characteristics of MDSCs in lung cancer are poorly understood. Objectives: We prospectively investigated MDSCs and inflammatory factors in tumor and peripheral blood samples from patients with resectable non–small cell lung cancer and studied their correlations with the disease prognosis. Methods: A complex analysis of MDSC subsets and inflammatory mediators was performed using flow cytometry and a Bio-Plex assay. Measurements and Main Results: A significant increase in the frequency of circulating monocytic (M)-MDSCs was observed in the patients with non–small cell lung cancer compared with the healthy donors (HDs). Moreover, the frequencies of M- and polymorphonuclear (PMN)-MDSCs were higher in tumors than in the peripheral blood of the same patients. This accumulation was associated with elevated concentrations of inflammatory mediators involved in MDSC migration to and activation in the tumor microenvironment. An analysis of the MDSC immunosuppressive pattern showed increased programmed death-ligand 1 expression on circulating cells from patients compared with HDs. Tumor PMN-MDSCs displayed higher programmed death-ligand 1 expression levels than the same cells in the peripheral blood. The frequency of CCR5 (C-C chemokine receptor 5) expression on circulating M-MDSCs was significantly higher in the patients than in the HDs. Clinical data analysis revealed negative correlations between recurrence-free survival and the frequencies of PMN-MDSCs and CCR5+ M-MDSCs in the circulation but not in tumors. Conclusions: Our findings suggest that the level of MDSCs in the peripheral blood but not in tumor tissues predicts recurrence after surgery.

Background: The best therapy for patients with stage I non-small cell lung cancer (NSCLC) who are medically unfit for lobectomy or prefer not to undergo surgery has not yet been demonstrated. Objectives: We analyzed data from our prospective database to evaluate the recurrence and survival rates and assess the extent to which the type of treatment explains outcome differences. Methods: This study included 116 patients with histologically proven clinical stage I NSCLC who were treated with sublobar resection (SLR; n = 42), radiofrequency ablation (RFA; n = 25) or radiotherapy (RT; n = 49) between 2009 and 2013. The primary end point was the time to primary tumor recurrence (PR). Kaplan-Meier curves and Cox regression were used to compare the recurrence patterns and survivals after adjustments for potential confounders. Results: The SLR patients were younger and exhibited better performance status. The RT patients had larger tumors. After adjusting for age and tumor size, there were differences between the different treatments in terms of the PR rate, but no differences were observed in overall (OS) or disease-free survival. The hazard ratio for PR comparing SLR versus RT adjusted for age and tumor size was 2.73 (95% confidence interval, CI, 0.72-10.27) and that for SLR versus RFA was 7.57 (95% CI 1.94-29.47). Conclusions: Our study suggests that SLR was associated with a higher primary tumor control rate compared to RFA or RT, although the OSs were not different. These results should be confirmed in prospective trials.

Original Article Multimodal therapy of epithelioid pleural mesothelioma: improved survival by changing the surgical treatment approach Laura V. Klotz, Hans Hoffmann, Rajiv Shah, Florian Eichhorn, Christiane Gruenewald, Elena L. Bulut, Raffaella Griffo, Thomas Muley, Petros Christopoulos, Philip Baum, Peter Huber, Seyer Safi, Marc Kriegsmann, Michael Thomas, Helge Bischoff, Hauke Winter, Martin E. Eichhorn

In this prospective study, we examined postoperative follow-up and preoperative IFN-γ T cell responses against 14 non-small cell lung cancer (NSCLC)-associated antigens in the blood of 51 patients with NSCLC, 7 patients with benign pulmonary tumors, and 10 tumor-free patients by enzyme-linked immunospot assay. The phenotype and function of T cells specific for tumor-associated antigens (TAAs) in the blood or tumor tissue of 9 NSCLC patients were characterized in detail using TNF-α, IL-2, and IFN-γ cytokine capture assays. We found that circulating TAA-specific T cells were significantly enriched in NSCLC compared with tumor-free patients. The most frequently recognized TAAs were Aurora kinase A, HER2/neu, NY-ESO-1, and p53. TNF-α was the most abundant cytokine secreted by TAA-specific T cells in the blood as well as by in situ-activated tumor-infiltrating lymphocytes, most of which were effector memory cells. The absence of TAA-reactive T cells identified patients at higher risk of tumor recurrence, irrespective of tumor stage (OR = 8.76, 95% CI: 1.57-34.79, p = 0.008). We conclude that pre-existing TAA-reactive circulating T cells are a strong independent prognostic factor for recurrence-free survival. These data may help discriminating high-risk from low-risk patients, improving prognostication, and redirecting adjuvant therapy. Our findings suggest the therapeutic relevance of Aurora kinase A, HER2/neu, NY-ESO-1, and p53 as targets for immunotherapy. This study is registered on Clinicaltrials.gov with trial identification number: NCT02515760.

Lung cancer remains a devastating disease with a poor clinical outcome. A biomarker signature which could distinguish lung cancer from metastatic disease and detect therapeutic failure would significantly improve patient management and allow for individualized, risk-adjusted therapeutic decisions. In this study, circulating Hsp70 levels were measured using ELISA, and the immunophenotype of the peripheral blood lymphocytes were measured using multiparameter flow cytometry, to identify a predictive biomarker signature for lung cancer patients pre- and post-operatively, in patients with lung metastases and in patients with COPD as an inflammatory lung disease. The lowest Hsp70 concentrations were found in the healthy controls followed by the patients with advanced COPD. Hsp70 levels sequentially increased with an advancing tumor stage and metastatic disease. In the early-recurrence patients, Hsp70 levels started to increase within the first three months after surgery, but remained unaltered in the recurrence-free patients. An early recurrence was associated with a significant drop in B cells and an increase in Tregs, whereas the recurrence-free patients had elevated T and NK cell levels. We conclude that circulating Hsp70 concentrations might have the potential to distinguish lung cancer from metastatic disease, and might be able to predict an advanced tumor stage and early recurrence in lung cancer patients. Further studies with larger patient cohorts and longer follow-up periods are needed to validate Hsp70 and immunophenotypic profiles as predictive biomarker signatures.