Background Consolidation treatment with an anti-PD-L1 antibody, durvalumab, following concurrent chemo-radiotherapy (cCRT) has become a new standard of care for locally advanced non-small cell lung cancer (NSCLC). The rationale of PD-L1 blockade after cCRT is based on preclinical evidence suggesting that chemotherapy and radiotherapy up-regulate tumoural PD-L1 expression, which has not been shown in clinical studies. Methods To examine alteration in tumoural PD-L1 expression (tumour proportion score, TPS) and density of stromal CD8-positive tumour-infiltrating lymphocytes (CD8 + TILs) after cCRT, paired NSCLC samples obtained before and after cCRT were reviewed in comparison with those obtained before and after drug therapy. Results PD-L1 expression was significantly up-regulated after cCRT (median TPS, 1.0 at baseline versus 48.0 after cCRT; P < 0.001), but not after drug therapy. There was no significant correlation between baseline TPS and post-cCRT TPS. CD8 + TIL density was significantly increased after cCRT (median, 10.6 versus 39.1; P < 0.001), and higher post-cCRT CD8 + TIL density was associated with a higher pathologic response and with a favourable survival ( P = 0.019). Conclusion Tumoural PD-L1 expression was up-regulated after cCRT, which provides pathologic rationale for PD-L1 blockade following cCRT to improve prognosis. Stromal CD8 + TIL density was also increased after cCRT, and higher post-cCRT CD8 + TIL density was a favourable prognostic indicator.

Background: Although immune checkpoint inhibitors (ICIs) for non-small cell lung cancer (NSCLC) have been established as one of standard therapy, the prognostic factors of ICIs remain unclear, aside from the programed cell death-ligand 1 (PD-L1) expression of tumor cells. The aim of this study was to determine the prognostic factors of ICIs. Methods: We analyzed the clinicopathological data of 44 cases of advanced NSCLC targeted with ICIs in our hospital, between February 2016 and February 2018, in order to determine the prognostic factors of ICIs. We also reviewed the literature regarding ICIs. Result: We retrospectively analyzed the 44 cases (26 nivolumab and 18 pembrolizumab cases). These patients were 38 men and 6 women, comprising 13 cases of adenocarcinoma, 29 squamous cell carcinoma and 2 unclassified types. Seven patients were using first-line therapy and while the others were using secondline therapy or later. Epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase (ALK) mutations were negative in all the cases. The response rate and disease control rate were 20.5% and 51.3%, respectively. The median progression-free survival time and median survival time were 146 days and 257 days, respectively. We observed five severe adverse effects (AEs) (three cases of interstitial pneumonia, one of liver dysfunction and one of adrenal failure), that were resolved by steroid pulse therapy. In multivariate analyses, the Eastern Cooperative Oncology Group performance status (ECOG PS), pathological type, standardized uptake value (SUV) on positron emission tomography (PET), white blood cell (WBC) count, neutrophil, neutrophil-to-lymphocyte ratio (NLR), lactate dehydrogenase (LDH) and albumin were independently prognostic factors. There were no significant differences in the prognosis between nivolumab and pembrolizumab. Conclusions: ICIs were effective in 44 treated NSCLC cases. Our analysis suggests that while ICIs are effective in treating patients, candidates must be carefully selected and cautiously observed.

Circulating tumor cell (CTC) is a potentially useful surrogate of micro-metastasis, but detection of rare tumor cells contaminated in a vast majority of normal hematologic cells remains technical challenges. To achieve effective detection of a variety of CTCs, we have developed a novel microfluidic system (CTC-chip) in which any antibody to capture CTCs is easily conjugated. In previous studies, we employed an antibody (clone E-1) against podoplanin that was strongly expressed on mesothelioma cells. The CTC-chip coated by the E-1 antibody (E1-chip) provided a modest sensitivity in detection of CTCs in malignant pleural mesothelioma (MPM). Here, to achieve a higher sensitivity, we employed a novel anti-podoplanin antibody (clone NZ-1.2). In an experimental model, MPM cells with high podoplanin expression were effectively captured with the CTC-chip coated by the NZ-1.2 antibody (NZ1.2-chip). Next, we evaluated CTCs in the peripheral blood sampled from 22 MPM patients using the NZ1.2-chip and the E1-chip. One or more CTCs were detected in 15 patients (68.2%) with the NZ1.2-chip, whereas only in 10 patients (45.5%) with the E1-chip. Of noted, in most (92.3%, 12/13) patients with epithelioid MPM subtype, CTCs were positive with the NZ1.2-chip. The CTC-count detected with the NZ1.2-chip was significantly higher than that with the E1-chip (p = 0.034). The clinical implications of CTCs detected with the NZ1.2-chip will be examined in a future study.

Detection of rare tumor cells circulating in the blood (CTCs) presents technical challenges. CellSearch, the only approved system for clinical use, fails to capture epithelial cell adhesion molecule‐negative CTCs such as malignant pleural mesothelioma (MPM). We have developed a novel microfluidic device (CTC‐chip) in which any Ab to capture CTCs is conjugated. The CTC‐chip was coated with an Ab against podoplanin that is abundantly expressed on MPM. Circulating tumor cell‐detection performance was evaluated in experimental models in which MPM cells were spiked in blood sampled from a healthy volunteer and in clinical samples drawn from MPM patients. The CTC‐chip showed superior CTC‐detection performance over CellSearch in experimental models (sensitivity, 63.3%‐64.5% vs 0%‐1.1%; P < .001) and in clinical samples (CTC‐positivity, 68.8% vs 6.3%; P < .001). A receiver operating characteristic (ROC) analysis showed that the CTC test provided a significant diagnostic performance in discrimination of unresectable disease from resectable disease (area under the ROC curve, 0.851; P = .003). The higher CTC count (≥2 cells/mL) was significantly associated with a poor prognosis (P = .030). The novel CTC‐chip enabled sensitive detection of CTCs, which provided significant diagnostic and prognostic information in MPM.

The prognostic impact of tumoral programmed death-ligand 1 (PD-L1) expression in correlation with neutrophil-to-lymphocyte ratio (NLR) was retrospectively assessed in 83 patients with completely resected stage I squamous cell carcinoma of the lung, as PD-L1 is a potent regulator of cancer immunity and NLR is a potential surrogate of immune status. Forty-three patients (51.8%) had tumor with positive PD-L1 expression. There was no significant correlation between PD-L1 expression and NLR. PD-L1-positivity failed to provide a significant prognostic impact (overall survival [OS] rate at 5 years, 53.0% in PD-L1-positive patients versus 70.1% in PD-L1-negative patients; P = 0.117). Among NLRlow (<2.2) patients, however, PD-L1-positivity was significantly correlated with a poor prognosis (OS rate at 5 years, 46.1% versus 86.0%; P = 0.020). In contrast, among NLR-high (≥2.2) patients, PD-L1-positivity provided no prognostic impact (P = 0.680). When NLR status and tumoral PD-L1 status were combined, "NLR-low and PD-L1-negative" was a significant and independent factor to predict a favorable recurrence-free survival (hazard ratio, 0.237 [95% confidence interval, 0.083 to 0.674]; P = 0.007) and OS (hazard ratio, 0.260 [0.091 to 0.745]; P = 0.012). These results suggest the prognostic impact of tumoral PD-L1 expression might be influenced by the status of NLR. open Scientific RepoRtS | (2020) 10:1243 | https://doi.org/10.1038/s41598-019-57321-x www.nature.com/scientificreports www.nature.com/scientificreports/ (NLR), which is easily calculated by dividing the number of neutrophils by number of lymphocytes, is a potential surrogate of systemic inflammation. Many clinical studies revealed that high NLR was associated with a poor prognosis in NSCLC 10,11 . Recently, the NLR has merged as an indicator of immune status, as it is associated with the survival benefit of PD-1/PD-L1 inhibitors [12][13][14] . Here, we examined the prognostic impact of tumoral PD-L1 expression status in correlation with NLR in early-stage lung squamous cell carcinoma. ResultsDistribution of NLR and cut-off value for prognostic analyses. The NLR value of each case was indicated in Fig. 1. The receiver operating characteristic (ROC) curve analysis showed that NLR provided a significant but modest diagnostic performance to predict death (are under ROC curve [AUC-ROC], 0.643; P = 0.029) ( Fig. 1). Based on the ROC curve, the median value (2.2) was employed as the cut-off value to classify each patient into NLR-high (NLR, 2.2 or higher) or NLR-low (NLR, less than 2.2) patient in further survival analyses (Fig. 1).Recurrence-free survival (RFS) and overall survival (OS) according to NLR status. The NLR provided a significant but modest prognostic impact for overall survival (OS) (P = 0.042), and its prognostic impact did not reach a statistical significance for recurrence-free survival (RFS) (P = 0.094) (Fig. 2). PD-L1 expression (tumor proportion score, TPS) in correlation with other patient character-istics. The distribution of TPS was indicated in Fig. 1,...