Clinical Lung Cancer Research Articles

Additive Antiproliferative and Antiangiogenic Effects of Metformin and Pemetrexed in a Non-Small-Cell Lung Cancer Xenograft Model.

Lung cancer is heterogeneous and challenging to cope with once it has progressed. Chemotherapy is the first step once no active driver mutation has been discovered. Non-antitumor drugs have been found to be beneficial when used as adjuvants to chemotherapy. In this study, the additive effect and mechanism of metformin combined with pemetrexed in non-small-cell lung cancer (NSCLC) cells were elucidated. Three NSCLC cell lines, A549, H1975, and HCC827, were used to analyze tumor cell proliferation, colony formation and the cell cycle in vitro when exposed to metformin alone, pemetrexed alone or their combination. We found that combination treatment in three cell lines exerted antiproliferative effects through cell cycle arrest in the S phase. An ex vivo chicken chorioallantoic membrane (CAM) assay was used to examine the antiangiogenic effect of metformin combined with pemetrexed on vascular structure formation. We further created an A549 orthotopic xenograft model with an in vivo imaging system (IVIS) and explored the associated indicators involved in the tumorigenic process. The in vitro results showed that the combination of metformin and pemetrexed exhibited an antiproliferative effect in reducing cell viability and colony formation, the downregulation of cyclin D1 and A2 and the upregulation of CDKN1B, which are involved in the G1/S phase. For antiangiogenic effects, the combination therapy inhibited the vascular structure, as proven by the CAM assay. We elucidated that combination therapy could target VEGFA and Endoglin by RT-qPCR, ELISA and histopathological findings in an A549 orthotopic NSCLC xenograft model. Our research demonstrated the additive antiproliferative and antiangiogenic effects of the combination of metformin with pemetrexed in NSCLC and could be applied to clinical lung cancer therapy.

Integrative Analysis of Genome, 3D Genome, and Transcriptome Alterations of Clinical Lung Cancer Samples

Genomic studies of cancer cell alterations, such as mutations, copy number variations (CNVs), and translocations, greatly promote our understanding of the genesis and development of cancers. However, the 3D genome architecture of cancers remains less studied due to the complexity of cancer genomes and technical difficulties. To explore the 3D genome structure in clinical lung cancer, we performed Hi-C experiments using paired normal and tumor cells harvested from patients with lung cancer, combining with RNA sequenceing analysis. We demonstrated the feasibility of studying 3D genome of clinical lung cancer samples with a small number of cells (1 × 104), compared the genome architecture between clinical samples and cell lines of lung cancer, and identified conserved and changed spatial chromatin structures between normal and cancer samples. We also showed that Hi-C data can be used to infer CNVs and point mutations in cancer. By integrating those different types of cancer alterations, we showed significant associations between CNVs, 3D genome, and gene expression. We propose that 3D genome mediates the effects of cancer genomic alterations on gene expression through altering regulatory chromatin structures. Our study highlights the importance of analyzing 3D genomes of clinical cancer samples in addition to cancer cell lines and provides an integrative genomic analysis pipeline for future larger-scale studies in lung cancer and other cancers.

Oncological clearance of minimally invasive approaches for clinical N0 non-small cell lung cancer

Oncological clearance of minimally invasive approaches for clinical N0 non-small cell lung cancer

Oncological clearance of minimally invasive lobectomy for clinical N0 non-small cell lung cancer: the role of robotic surgery

Oncological clearance of minimally invasive lobectomy for clinical N0 non-small cell lung cancer: the role of robotic surgery

Lin28A promotes the proliferation and stemness of lung cancer cells via the activation of mitogen-activated protein kinase pathway dependent on microRNA let-7c.

BackgroundAmong patients with lung cancer, metastatic and relapsed cases account for the largest proportion of disease-associated deaths. Tumor metastasis and relapse are believed to originate from cancer stem cells (CSCs), which have the capacity to be highly proliferative and invasive. In our previous studies, we established a conditional basement membrane extract-based (BME-based) 3-dimensional (3D) culture system to mimic the tumor growth environment in vivo and further amplified lung cancer stem cells (LCSCs) in our system. However, the molecular mechanisms of LCSC amplification and development in our 3D culture system have not been fully uncovered.MethodWe established the conditional 3D culture system to amplify LCSCs in other lung cancer cell lines, followed by examining the expression of Lin28A and let-7 microRNAs in them. We also explored the expression of Lin28A and let-7 microRNAs in LCSCs from clinical lung cancer tissue samples and even analyzed the correlation of Lin28A/let-7c and patients’ survival outcomes. We further constructed A549 cells either knockdown of Lin28A or overexpression of let-7c, followed by investigating stemness marker gene expression, and stemness phenotypes including mammosphere culture, cell migration and invasion in vitro, as well as tumorigenicity in vivo.ResultsHere, we observed that Lin28A/let-7c was dysregulated in LCSCs in both the 3D culture system and lung cancer tissues. Further, the abnormal expression of Lin28A/let-7c was correlated with poor survival outcomes. Via the construction of A549 cells with let-7c over-expression, we found that let-7c inhibited the maintenance of LCSC properties, while the results of Lin28A knockdown showed that Lin28A played a critical role in the enrichment and proliferation of LCSCs via mitogen-activated protein kinase (MAPK) signaling pathway. Importantly, we found that LCSCs with knockdown of Lin28A or over-expression of let-7c exhibited inhibited carcinogenesis and disrupted expansion in vivo.ConclusionsOur study uncovered the functions and mechanisms of the Lin28A/let-7c/MAPK signaling pathway in promoting the proliferation and cancer stemness of LCSCs, which might be a potential therapeutic target for reducing and even eliminating LCSCs in the future.

Complex Segmentectomy for Hypermetabolic Clinical Stage IA Non-Small Cell Lung Cancer

BackgroundDue to its invasiveness, the indications for “complex segmentectomy” for radiologically hypermetabolic (high maximum standard uptake value) non-small cell lung cancer (NSCLC) remain controversial. This study compared the outcomes after complex segmentectomy and lobectomy in these patients. MethodsWe retrospectively reviewed 717 patients with radiologically hypermetabolic (maximum standardized uptake value ≥2.5), clinical stage IA NSCLC who underwent complex segmentectomy (n = 61) or location-adjusted lobectomy (n = 656) at three institutions from 2010 to 2019. Postoperative outcomes were analyzed for all patients and their propensity score matched pairs. Factors affecting oncologic outcomes were assessed by Kaplan-Meier estimates and Cox proportional hazards regression analyses. ResultsThe prognosis of patients undergoing complex segmentectomy was not significantly different from that of patients undergoing lobectomy (5-year cancer-specific survival rate, 89.9% vs 91.1%, P = .98; and 5-year recurrence-free interval rate, 83% vs 77.5%, P = .62) in the nonadjusted cohort. In 55 propensity score matched pairs, oncologic outcomes were not significantly different between patients undergoing complex segmentectomy (5-year cancer-specific survival, 89.9%; 5-year recurrence-free interval, 83%) and lobectomy (5-year cancer-specific survival, 83.6%; 5-year recurrence-free interval, 82.5%). Multivariable Cox regression analysis for recurrence-free interval revealed no significant differences between oncologic outcomes associated with complex segmentectomy and lobectomy (hazard ratio, 0.84; 95% confidence interval, 0.25 to 2.14; P = .74). ConclusionsOncologic outcomes of complex segmentectomy and lobectomy were not significantly different for patients with radiologically hypermetabolic, clinical stage IA NSCLC patients. Complex segmentectomy can treat high maximum standardized uptake value, clinical stage IA lung cancers without compromising oncologic results.

Suppression of m6A mRNA modification by DNA hypermethylated ALKBH5 aggravates the oncological behavior of KRAS mutation/LKB1 loss lung cancer

Oncogenic KRAS mutations combined with the loss of the LKB1 tumor-suppressor gene (KL) are strongly associated with aggressive forms of lung cancer. N6-methyladenosine (m6A) in mRNA is a crucial epigenetic modification that controls cancer self-renewal and progression. However, the regulation and role of m6A modification in this cancer are unclear. We found that decreased m6A levels correlated with the disease progression and poor survival for KL patients. The correlation was mediated by a special increase in ALKBH5 (AlkB family member 5) levels, an m6A demethylase. ALKBH5 gain- or loss-of function could effectively reverse LKB1 regulated cell proliferation, colony formation, and migration of KRAS-mutated lung cancer cells. Mechanistically, LKB1 loss upregulated ALKBH5 expression by DNA hypermethylation of the CTCF-binding motif on the ALKBH5 promoter, which inhibited CTCF binding but enhanced histone modifications, including H3K4me3, H3K9ac, and H3K27ac. This effect could successfully be rescued by LKB1 expression. ALKBH5 demethylation of m6A stabilized oncogenic drivers, such as SOX2, SMAD7, and MYC, through a pathway dependent on YTHDF2, an m6A reader protein. The above findings were confirmed in clinical KRAS-mutated lung cancer patients. We conclude that loss of LKB1 promotes ALKBH5 transcription by a DNA methylation mechanism, reduces m6A modification, and increases the stability of m6A target oncogenes, thus contributing to aggressive phenotypes of KRAS-mutated lung cancer.

Patient adherence to LungRADS recommendations at an academic institution.

e18592 Background: The National Lung Screening Trial (NLST) demonstrated a 20% reduction in lung cancer mortality when screened with low dose computed tomography (LDCT) as opposed to chest radiography. Notably, participants’ adherence to the screening protocol was 90%. To date, published evidence on the adherence of patients enrolled in clinical lung cancer screening (LCS) programs to LungRADS recommendations is limited. We investigate the adherence rate at our institution and determine the predictors of non-adherence to LungRADS recommendations. Methods: We performed a retrospective analysis on patients aged 50-80 years at time of baseline screen with initial screening exam at our institution between Jan 1, 2015 and Jan 12, 2021. Patients were excluded if 1) their follow-up period was insufficient to determine adherence as of Jan 28, 2021, 2) the follow-up recommendation was inconsistent with LungRADS guidelines, or 3) they died before the expected follow-up date. Adherence was defined as completion of recommended or more invasive follow-up at our institution within 12 months for LungRADS 0, 15 months for LungRADS 1/2, 9 months for LungRADS 3, 5 months for LungRADS 4A, and 3 months for LungRADS 4B/4X. A univariate logistic regression was used to determine predictors of non-adherence. Results: Among the 2120 eligible patients, 1266 (60%) were male and 854 (40%) were female with a median age of 65 at the baseline screen. One thousand four hundred and seventy-seven (70%) patients identified as White, 286 (13%) declared another racial group, and 357 (17%) did not disclose their race. One hundred and nine (5%) patients identified as Hispanic and 165 (8%) patients did not state their ethnicity. There were 1113 (53%) former smokers, 748 (35%) current smokers, and 259 (12%) patients of unspecified smoking status. Median tobacco exposure was 30 pack years (range 0.15 to 240). Fifty-seven percent of patients had private or commercial insurance while 39% had Medicare as primary insurance (3 patients were unspecified). The distribution of baseline LungRADS scores was 0: < 1%, 1: 14%, 2: 71%, 3: 7%, 4A: 4%, 4B: 2%, and 4X: < 1%. Overall adherence was 31% with 0: 38%, 1: 21%, 2: 27%, 3: 46%, 4A: 68%, 4B: 80%, and 4X: 100%. Of the 1463 non-adherent patients, 528 completed a follow-up exam beyond the expected date while 935 did not have any follow-up before the end of the study. Patients who were over 65 at baseline screen (OR = 1.34, 95% CI: 1.11, 1.61), former smokers (OR = 1.24, 95% CI: 1.02, 1.52), had Medicare insurance (OR = 1.35 95% CI: 1.12, 1.63), or had LungRADS 3/4 (referent: LR 1/2, OR = 4.29, 95% CI: 3.32, 5.55) were more likely to be adherent. Conclusions: Patient adherence to LungRADS recommendations at time of baseline screen in clinical practice is suboptimal, particularly among those with negative screens (LungRADS 1/2), with a non-adherence rate of > 70%. Baseline LungRADS scores, age, smoking status, and insurance are predictive of LCS non-adherence.

Circulating CD15+ LOX-1+ PMN-MDSCs are a potential biomarker for the early diagnosis of non-small-cell lung cancer.

Non-small-cell lung cancer (NSCLC) is the most common clinical lung cancer. Polymorphonuclear-myeloid derived suppressor cells (PMN-MDSCs), which are the major population of MDSCs, are involved in NSCLC progression. Recently, it was found that lectin-type oxidized LDL receptor 1 (LOX-1) could identify human PMN-MDSCs. However, the role of CD15+ LOX-1+ PMN-MDSCs in NSCLC early diagnosis has not been revealed. Here, we tried to confirm the application of the newly identified CD15+ LOX-1+ PMN-MDSCs in the early diagnosis of NSCLC. Flow cytometry (FCM) was used to detect the proportion of CD15+ LOX-1+ PMN-MDSCs in the peripheral blood (PB) of healthy controls (HC) and NSCLC patients. The correlation of CD15+ LOX-1+ PMN-MDSC frequency with levels of cytokeratin 19-fragments (CYFRA21-1), carcinoembryonic antigen (CEA), and carbohydrate antigen 125 (CA125) was analysed. Receiver operating characteristic (ROC) curve was used to estimate the diagnostic efficacy of CD15+ LOX-1+ PMN-MDSCs for NSCLC. Additionally, the association of CD15+ LOX-1+ PMN-MDSC frequency with NSCLC prognosis/recurrence after surgery was explored. The proportion of CD15+ LOX-1+ PMN-MDSCs increased in PB of NSCLC patients. CD15+ LOX-1+ PMN-MDSC proportion was positively correlated with levels of CEA, CA125 and CYFRA21-1. Detection of PMN-MDSC percentage in PB owed high sensitivity and specificity for NSCLC diagnosis. The proportion of CD15+ LOX-1+ PMN-MDSCs decreased in patients after surgery. The frequency of CD15+ LOX-1+ PMN-MDSCs was lower in NSCLC patients without recurrence compared to those with recurrence after surgery. Circulating CD15+ LOX-1+ PMN-MDSCs are a potential diagnostic marker for NSCLC, and are associated with NSCLC prognosis and recurrence after surgery.

Improving the Subtype Classification of Non-small Cell Lung Cancer by Elastic Deformation Based Machine Learning.

Non-invasive image-based machine learning models have been used to classify subtypes of non-small cell lung cancer (NSCLC). However, the classification performance is limited by the dataset size, because insufficient data cannot fully represent the characteristics of the tumor lesions. In this work, a data augmentation method named elastic deformation is proposed to artificially enlarge the image dataset of NSCLC patients with two subtypes (squamous cell carcinoma and large cell carcinoma) of 3158 images. Elastic deformation effectively expanded the dataset by generating new images, in which tumor lesions go through elastic shape transformation. To evaluate the proposed method, two classification models were trained on the original and augmented dataset, respectively. Using augmented dataset for training significantly increased classification metrics including area under the curve (AUC) values of receiver operating characteristics (ROC) curves, accuracy, sensitivity, specificity, and f1-score, thus improved the NSCLC subtype classification performance. These results suggest that elastic deformation could be an effective data augmentation method for NSCLC tumor lesion images, and building classification models with the help of elastic deformation has the potential to serve for clinical lung cancer diagnosis and treatment design.

Regional Variation in Treatment for Highest-Risk Patients With Non-Small Cell Lung Cancer

BackgroundNon-small cell lung cancer patients with multiple high-risk socioeconomic factors experience treatment and survival disparities. We aim to assess whether disparities in treatment and survival vary by region for patients with 3 or more high-risk socioeconomic factors. MethodsThe National Cancer Database was queried for patients with clinical stage I-IIA non-small cell lung cancer diagnosed between 2010 and 2015. Patients were categorized into 3 groups: standard treatment, nonstandard treatment, and no curative treatment. Multivariable logistic regression was used to evaluate regional differences in treatment. Cox proportional hazards regression and the Kaplan-Meier method were used for survival analysis. All statistical tests were 2-sided. ResultsA total of 93,211 patients met inclusion criteria. For patients with 3 or more high-risk socioeconomic factors, the odds of nonstandard treatment were significantly greater in 6 regions compared with New England, greatest in West North Central (odds ratio 2.09, P < .001). The odds of no curative treatment were significantly greater in 7 regions compared with New England, greatest in West South Central (odds ratio 3.56, P < .001). West North Central was associated with the highest risk of all-cause mortality compared with New England (hazard ratio 1.10, P < .001), and Middle Atlantic was associated with the lowest (hazard ratio 0.86, P < .001). The 5-year overall survival was longest in Middle Atlantic (60.8%) and shortest in Mountain (36.8%). ConclusionsPatients with 3 or more high-risk socioeconomic factors experience treatment and survival disparities across the United States, though disparities are more pronounced in certain regions. Regional interventions may help mitigate disparities among highest risk non-small cell lung cancer patients.

Induction of APOBEC3 Exacerbates DNA Replication Stress and Chromosomal Instability in Early Breast and Lung Cancer Evolution.

APOBEC3 enzymes are cytosine deaminases implicated in cancer. Precisely when APOBEC3 expression is induced during cancer development remains to be defined. Here we show that specific APOBEC3 genes are upregulated in breast ductal carcinoma in situ, and in preinvasive lung cancer lesions coincident with cellular proliferation. We observe evidence of APOBEC3-mediated subclonal mutagenesis propagated from TRACERx preinvasive to invasive non-small cell lung cancer (NSCLC) lesions. We find that APOBEC3B exacerbates DNA replication stress and chromosomal instability through incomplete replication of genomic DNA, manifested by accumulation of mitotic ultrafine bridges and 53BP1 nuclear bodies in the G1 phase of the cell cycle. Analysis of TRACERx NSCLC clinical samples and mouse lung cancer models revealed APOBEC3B expression driving replication stress and chromosome missegregation. We propose that APOBEC3 is functionally implicated in the onset of chromosomal instability and somatic mutational heterogeneity in preinvasive disease, providing fuel for selection early in cancer evolution. SIGNIFICANCE: This study reveals the dynamics and drivers of APOBEC3 gene expression in preinvasive disease and the exacerbation of cellular diversity by APOBEC3B through DNA replication stress to promote chromosomal instability early in cancer evolution.This article is highlighted in the In This Issue feature, p. 2355.

CEBPγ facilitates lamellipodia formation and cancer cell migration through CERS6 upregulation.

Ceramide synthase 6 (CERS6) promotes lung cancer metastasis by stimulating cancer cell migration. To examine the underlying mechanisms, we performed luciferase analysis of the CERS6 promoter region and identified the Y‐box as a cis‐acting element. As a parallel analysis of database records for 149 non–small‐cell lung cancer (NSCLC) cancer patients, we screened for trans‐acting factors with an expression level showing a correlation with CERS6 expression. Among the candidates noted, silencing of either CCAAT enhancer‐binding protein γ (CEBPγ) or Y‐box binding protein 1 (YBX1) reduced the CERS6 expression level. Following knockdown, CEBPγ and YBX1 were found to be independently associated with reductions in ceramide‐dependent lamellipodia formation as well as migration activity, while only CEBPγ may have induced CERS6 expression through specific binding to the Y‐box. The mRNA expression levels of CERS6, CEBPγ, and YBX1 were positively correlated with adenocarcinoma invasiveness. YBX1 expression was observed in all 20 examined clinical lung cancer specimens, while 6 of those showed a staining pattern similar to that of CERS6. The present findings suggest promotion of lung cancer migration by possible involvement of the transcription factors CEBPγ and YBX1.

Role of surgery in a case-control study of patients with clinical stage IIIA small cell lung cancer.

BackgroundThe role of surgery in the multidisciplinary treatment of clinical stage IIIA small cell lung cancer is yet to be verified. This study was performed to determine the benefit of surgery in patients with stage IIIA small cell lung cancer.MethodsPatients diagnosed with stage IIIA small cell lung cancer at Shanghai Pulmonary Hospital from 2005 to 2015 were included and divided into two groups: the surgery with neoadjuvant and adjuvant chemotherapy group and the concurrent chemo-radiotherapy group. Overall survival was compared between the two groups. A multivariate Cox regression model was constructed to evaluate factors associated with overall survival.ResultsOf 69 patients with stage IIIA small cell lung cancer during the study period, 40 patients (58%) underwent surgery with neoadjuvant and adjuvant chemotherapy, and 29 patients (42%) underwent concurrent chemo-radiotherapy. Patients in the surgery with neoadjuvant and adjuvant chemotherapy group had a longer overall survival compared with patients in the concurrent chemo-radiotherapy group (median survival: 33.1 vs. 16.2 months, respectively; 2-year overall survival: 44.2% vs. 14.9%, respectively; log-rank: P=0.045). A multivariate analysis revealed that surgery with neoadjuvant and adjuvant chemotherapy (hazard ratio: 0.374; 95% confidence interval: 0.173–0.808, P=0.012) was independently associated with overall survival.ConclusionsPatients with stage IIIA small cell lung cancer treated with surgical resection plus chemotherapy demonstrated longer overall survival compared with those who underwent concurrent chemo-radiotherapy. Surgery may be an option for clinical stage IIIA small cell lung cancer after induction chemotherapy in selected patients.

Outcome of thoracoscopic anatomical sublobar resection under 3-dimensional computed tomography simulation.

Previous studies have reported the feasibility and efficacy of thoracoscopic anatomical sublobar resection under three-dimensional computed tomography (3DCT) simulation; however, its long-term outcomes have not been clearly established in primary lung cancer. This study aimed to evaluate the long-term outcomes of this technique. We retrospectively reviewed data from 112 consecutive patients with selected clinical stage IA non-small cell lung cancer (NSCLC) who underwent thoracoscopic anatomical sublobar resection from 2004 to 2014. This procedure was planned using preoperative 3DCT simulation to ensure sufficient surgical margins and enabled tailor-made surgery for each patient. Patients who had predominantly ground glass opacity lung cancers underwent anatomical sublobar resection as a curative-intent resection. Other patients who were high-risk candidates for lobectomy underwent anatomical sublobar resection as a compromised limited resection. Of the 112 cases, 82 had a curative-intent resection, while 30 had a compromised limited resection. Recurrence occurred in only 2 cases (1.8%), both of which were in the compromised limited group. A second primary lung cancer was observed in 5 cases (4.5%). Of the 5 patients, 4 underwent surgery for a second cancer and had no recurrence. The 5-year overall survival, lung cancer-specific overall survival, and recurrence-free survival rates were 92.5%, 100%, and 98.2%, respectively, for all cases; 97.6%, 100%, and 100%, respectively, in the curative-intent group; and 75.8%, 100% and 92.6%, respectively, in the compromised limited group. Thoracoscopic anatomical sublobar resection under 3DCT simulation may be an acceptable alternative treatment in selected patients with NSCLC. Clinical registration number: IRB No. 2020-98 (Dated: 2020.6.30).

Notch1 Deficiency Induces Tumor Cell Accumulation Inside the Bronchiolar Lumen and Increases TAZ Expression in an Autochthonous Kras LSL-G12V Driven Lung Cancer Mouse Model.

Purpose: Abrogation of Notch signaling, which is pivotal for lung development and pulmonary epithelial cell fate decisions was shown to be involved in the aggressiveness and the differentiation of lung carcinomas. Additionally, the transcription factors YAP and TAZ which are involved in the Hippo pathway, were recently shown to be tightly linked with Notch signaling and to regulate the cell fate in epidermal stem cells. Thus, we aim to elucidate the effects of conditional Notch1 deficiency on carcinogenesis and TAZ expression in lung cancer. Methods: We investigated the effect of conditional Cre-recombinase mediated Notch1 knock-out on lung cancer cells in vivo using an autochthonous mouse model of lung adenocarcinomas driven by Kras LSL-G12V and comprehensive immunohistochemical analysis. In addition, we analyzed clinical samples and human lung cancer cell lines for TAZ expression and supported our findings by publicly available data from The Cancer Genome Atlas (TCGA). Results: In mice, we found induction of papillary adenocarcinomas and protrusions of tumor cells from the bronchiolar lining upon Notch1 deficiency. Moreover, the mutated Kras driven lung tumors with deleted Notch1 showed increased TAZ expression and focal nuclear translocation which was frequently observed in human pulmonary adenocarcinomas and squamous cell carcinomas of the lung, but not in small cell lung carcinomas. In addition, we used data from TCGA to show that putative inactivating NOTCH1 mutations co-occur with KRAS mutations and genomic amplifications in lung adenocarcinomas. Conclusion: Our in vivo study provides evidence that Notch1 deficiency in mutated Kras driven lung carcinomas contributes to lung carcinogenesis in a subgroup of patients by increasing TAZ expression who might benefit from TAZ signaling blockade.

Clinical T1aN0M0 lung cancer: differences in clinicopathological patterns and oncological outcomes based on the findings on high-resolution computed tomography

To elucidate the clinicopathological characteristics and oncological outcomes of clinical T1aN0M0 (c-T1N0M0) lung cancer based on the newest 8th TNM classification. A total of 257 patients with c-T1aN0M0 lung cancer were retrospectively included in this study. According to the solid component size manifesting on the high-resolution computed tomography (HRCT), all lesions were classified as the pure ground-glass nodule (pure-GGN) with a diameter > 3 cm (n = 19), part-solid (n = 174), and pure-solid (n = 64) groups. We evaluated the prognostic impact of clinicopathologic variables including radiological presentations by establishing Cox proportional hazards model. When we evaluated the prognostic impact based on the radiological subtypes, the 5-year recurrence-free survival (RFS) and overall survival (OS) were significantly different among pure-GGN, part-solid, and pure-solid groups (RFS: 100% versus 95.4% versus 76.6%, p < 0.0001; OS: 100% versus 98.9% versus 87.5%, p < 0.0001). Cox regression analysis revealed the preoperative carcinoembryonic antigen (CEA) level and consolidation tumor ratio (CTR) were independently significant prognosticators related to RFS and OS. Furthermore, a receiver operating characteristic (ROC) verified the CTR (area under ROC [AUC] 0.784, 95%CI 0.697-0.869) was equipped with good performance to predict the postoperative recurrence with a cutoff point at 0.5. Lung cancer with higher CTR tended to be associated with lower survival in the c-T1aN0M0 stage. For the c-T1aN0M0 lung cancer, pulmonary nodules manifested as the pure-GGN and part-solid subtypes had an excellent prognosis and may be considered as the "early-stage" cancer, whereas those with pure-solid appearance were associated with the high risk of recurrence despite the sub-centimeter size. • Radiological subtypes could further stratify the risk of lung cancer in cT1a. • Sub-solid nodule has a favorable survival in c-T1a lung cancer, whereas pure-solid nodule is not always "early-stage" lung cancer and is relatively prone to postoperative recurrence despite the sub-centimeter size. • The preoperative CEA level and CTR are valuable prognosticators to predict the recurrence in c-T1a lung cancer.

Reproducibility of lung nodule radiomic features: Multivariable and univariable investigations that account for interactions between CT acquisition and reconstruction parameters.

Recent studies have demonstrated a lack of reproducibility of radiomic features in response to variations in CT parameters. In addition, reproducibility of radiomic features has not been well established in clinical datasets. We aimed to investigate the effects of a wide range of CT acquisition and reconstruction parameters on radiomic features in a realistic setting using clinical low dose lung cancer screening cases. We performed univariable and multivariable explorations to consider the effects of individual parameters and the simultaneous interactions between three different acquisition/reconstruction parameters of radiation dose level, reconstructed slice thickness, and kernel. A cohort of 89 lung cancer screening patients were collected that each had a solid lung nodule >4mm diameter. A computational pipeline was used to perform a simulation of dose reduction of the raw projection data, collected from patient scans. This was followed by reconstruction of raw data with weighted filter back projection (wFBP) algorithm and automatic lung nodule detection and segmentation using a computer-aided detection tool. For each patient, 36 different image datasets were created corresponding to dose levels of 100%, 50%, 25%, and 10% of the original dose level, three slice thicknesses of 0.6mm, 1mm, and 2mm, as well as three reconstruction kernels of smooth, medium, and sharp. For each nodule, 226 well-known radiomic features were calculated at each image condition. The reproducibility of radiomic features was first evaluated by measuring the intercondition agreement of the feature values among the 36 image conditions. Then in a series of univariable analyses, the impact of individual CT parameters was assessed by selecting subsets of conditions with one varying and two constant CT parameters. In each subset, intraparameter agreements were assessed. Overall concordance correlation coefficient (OCCC) served as the measure of agreement. An OCCC≥0.9 implied strong agreement and reproducibility of radiomic features in intercondition or intraparameter comparisons. Furthermore, the interaction of CT parameters in impacting radiomic feature values was investigated via ANOVA. All included radiomic features lacked intercondition reproducibility (OCCC<0.9) among all the 36 conditions. Out of 226 radiomic features analyzed, only 17 and 18 features were considered reproducible (OCCC≥0.9) to dose and kernel variation, respectively, within the corresponding condition subsets. Slice thickness demonstrated the largest impact on radiomic feature values where only one to five features were reproducible at a few condition subsets. ANOVA revealed significant interactions (P<0.05) between CT parameters affecting the variability of >50% of radiomic features. We systematically explored the multidimensional space of CT parameters in affecting lung nodule radiomic features. Univariable and multivariable analyses of this study not only showed the lack of reproducibility of the majority of radiomic features but also revealed existing interactions among CT parameters, meaning that the effect of individual CT parameters on radiomic features can be conditional upon other CT acquisition and reconstruction parameters. Our findings advise on careful radiomic feature selection and attention to the inclusion criteria for CT image acquisition protocols within the datasets of radiomic studies.

Spanish Lung Cancer Group SCAT trial: surgical audit to lymph node assessment based on IASLC recommendations

BackgroundThe Spanish Customized Adjuvant Therapy (SCAT) trial assessed the role of individualized adjuvant therapy in clinical N0 incidental pN1 and/or N2 non-small cell lung cancer (NSCLC) completely resected. We assessed surgical topics with an in-depth analysis of quality of lymphadenectomy based on International Association for the Study of Lung Cancer (IASLC) recommendations.MethodsPatients with information about lymphadenectomy available were included (N=451). Prospectively collected data about tumor, type of resection, and postoperative morbidity and quality of lymph node dissection (LND) were retrospectively evaluated. Role of lymph node assessment on survival was analyzed using Kaplan-Meier curves, using regression models to identify prognostic factors.ResultsIn 33.7%, 17.7% and 49.9% of cases, regions 7, 10 and 11 respectively were not assessed. In 21.1% of patients, less than three lymph node regions were biopsied, while in 19.6% of patients less than six lymph nodes were assessed. In 53,4% of patients only one N1 region was evaluated. From patients with positive N2, 8.9% had no N1 regions biopsied. Twenty-nine percent of patients with at least one N2 lymph node resected shown the highest region involved. Thirty-day postoperative mortality was unknown. Five-year overall survival (OS) was 61.7% (95% CI: 55.4–67.4%), 51.5% (95% CI: 39.2–62.4%) and 42.3% (95% CI: 32.1–52.2%) for patients with N1, N2 and N1+N2 disease, respectively (P<0.01). Both number of lymph nodes resected and number of lymph nodes involved by tumor were significantly related to prognosis.ConclusionsIASLC recommendations for surgical resections were not followed in a high proportion of surgical procedures. Hilar and mediastinal lymph node assessment and involvement showed to impact prognosis. Surgical issues such as postoperative mortality could not be evaluated owing to trial design.

FGF16 regulated by miR-520b enhances the cell proliferation of lung cancer.

FGF16 is implicated in the progression of some specific types of cancers, such as embryonic carcinoma, ovarian cancer, and liver cancer. Yet, the function of FGF16 in the development of lung cancer remains largely unexplored. In this study, we present the novel function of FGF16 and the regulation of miR-520b on FGF16 in lung cancer progression. In clinical lung cancer tissues, FGF16 is overexpressed and its high level is negatively associated with the low level of miR-520b. Furthermore, both the transcription and translation levels of FGF16 are restrained by miR-520b in lung cancer cells. For the regulatory mechanism investigation, miR-520b is able to directly bind to the 3′-untranslated region (3′UTR) of FGF16 mRNA, leading to its mRNA cleavage in the cells. Functionally, miR-520b reduces the growth of lung cancer and its inhibitor anti-miR520b is able to promote the growth through competing endogenous miR-520b. Moreover, FGF16 silence using RNA interference is capable of doing great damage to anti-miR-520b-accelerated growth of lung cancer. Thus, our finding indicates that FGF16 is a new target gene of miR-520b in lung cancer. For lung cancer, FGF16 may serve as a novel biomarker and miR-520b/FGF16 may be useful in clinical treatment.