Lung cancer screening

The effect of the introduction of the national lung cancer screening program on short-term mortality in Korea

BACKGROUND

South Korea introduced the National Lung Cancer Screening Program (NLCSP) in 2019. This study investigated the effect of the NLCSP on one-year mortality in individuals with a history of lung cancer.

METHODS

This study used the 2018-2020 National Health Insurance Service claims data. The difference-in-differences approach was used to investigate the effect of participating in the NLCSP between the case and control groups before and after the intervention period. The case group included individuals aged between 54 and 74 years with a smoking history of ≥ 30 pack-years and the control group those aged between 54 and 74 years with a history of smoking of <30 pack-years and non-smokers. The pre-intervention period was from January 2018 to June 2019 and the post-intervention period from July 2019 to December 2020.

RESULTS

The introduction of the NLCSP was related to an overall decrease in one-year mortality (-3.21 % points, 95 % Confidence Interval (CI) -4.84 to -1.58). Specifically, this reduction was significant for lung cancer related mortality (lung cancer: -2.69 % points, 95 % CI -4.24 to -1.13). Furthermore, stronger associations were found in individuals of older age, residing in non-metropolitan areas, and who visited healthcare institutions in non-metropolitan areas.

CONCLUSION

The findings confirm a relationship between implementation of the NLCSP and one-year mortality in eligible individuals with a history of lung cancer, which is noteworthy considering that Korea is one of the first countries to include lung cancer into the national cancer screening program.

A Cross-Sectional Study on the Acceptability of Implementing a Lung Cancer Screening Program in Belgium

Lung cancer is the most common and deadliest cancer in the world, and its incidence is expected to grow. Nonetheless, this growth can be contained through smoking cessation programs and effective lung cancer screening programs. In 2018, Belgium had the seventh highest incidence of lung cancer in the world, with lung cancer incidence accounting for 11.8% of all cancers diagnosed and 23.8% of all cancer-related deaths that same year. The aims of this study were to determine the overall acceptability of a lung cancer screening program in the Flemish population and to determine the main factors that would influence the overall acceptability of such a program. A questionnaire-based cross-sectional study was performed in the Flemish population and distributed online and on paper. The results are presented with the variables of interest and the main outcome, i.e., the acceptability of participating in such a program if implemented. Odds ratios were used to compare acceptability between subgroups. A multivariate regression model was used to determine the key factors that would have the largest impact on the level of acceptability and, thus, on the possible efficiency of such a program. This study estimated that acceptability of participating in a lung cancer screening program was 92%. Irrespective of the smoking status, levels of acceptability were higher than 89%. The key factors which could significantly influence the acceptability of a lung cancer screening program were individuals with low education, low protective factor knowledge and total knowledge, and lung cancer screening reimbursement, which were significantly associated with acceptability (0.01, 0.001, 0.01, and 0.05 respectively). Low protective factor knowledge decreased the log odds of acceptability 3.08-fold. In conclusion, the acceptability of implementing a lung cancer screening program in Flanders seems to be extremely high and would be well received by all. When implementing such a program, policymakers should aim for it to be reimbursed, campaigns should be gender-specific, focused on those with lower educational and socioeconomic status, and there should be investment in increasing total knowledge about lung cancer and knowledge about protective factors.

Polygenic risk scores to stratify cancer screening should predict mortality not incidence

Population-based cancer screening programs such as mammography or colonscopy generally directed at all healthy individuals in a given age stratum. It has recently been proposed that cancer screening could be restricted to a high-risk subgroup based on polygenic risk scores (PRSs) using panels of single-nucleotide polymorphisms (SNPs). These PRSs were, however, generated to predict cancer incidence rather than cancer mortality and will not necessarily address overdiagnosis, a major problem associated with cancer screening programs. We develop a simple net-benefit framework for evaluating screening approaches that incorporates overdiagnosis. We use this methodology to demonstrate that if a PRS does not differentially discriminate between incident and lethal cancer, restricting screening to a subgroup with high scores will only improve screening outcomes in a small number of scenarios. In contrast, restricting screening to a subgroup defined as high-risk based on a marker that is more strongly predictive of mortality than incidence will often afford greater net benefit than screening all eligible individuals. If PRS-based cancer screening is to be effective, research needs to focus on identifying PRSs associated with cancer mortality, an unchartered and clinically-relevant area of research, with a much higher potential to improve screening outcomes.

Nationwide lung cancer screening with low-dose computed tomography: implementation and first results of the HUNCHEST screening program

OBJECTIVES

Lung cancer (LC) kills more people than any other cancer in Hungary. Hence, there is a clear rationale for considering a national screening program. The HUNCHEST pilot program primarily aimed to investigate the feasibility of a population-based LC screening in Hungary, and determine the incidence and LC probability of solitary pulmonary nodules.

METHODS

A total of 1890 participants were assigned to undergo low-dose CT (LDCT) screening, with intervals of 1 year between procedures. Depending on the volume, growth, and volume doubling time (VDT), screenings were defined as negative, indeterminate, or positive. Non-calcified lung nodules with a volume > 500 mm³ and/or a VDT < 400 days were considered positive. LC diagnosis was based on histology.

RESULTS

At baseline, the percentage of negative, indeterminate, and positive tests was 81.2%, 15.1%, and 3.7%, respectively. The frequency of positive and indeterminate LDCT results was significantly higher in current smokers (vs. non-smokers or former smokers; p < 0.0001) and in individuals with COPD (vs. those without COPD, p < 0.001). In the first screening round, 1.2% (n = 23) of the participants had a malignant lesion, whereas altogether 1.5% (n = 29) of the individuals were diagnosed with LC. The overall positive predictive value of the positive tests was 31.6%. Most lung malignancies were diagnosed at an early stage (86.2% of all cases).

CONCLUSIONS

In terms of key characteristics, our prospective cohort study appears consistent to that of comparable studies. Altogether, the results of the HUNCHEST pilot program suggest that LDCT screening may facilitate early diagnosis and thus curative-intent treatment in LC.

KEY POINTS

• The HUNCHEST pilot study is the first nationwide low-dose CT screening program in Hungary. • In the first screening round, 1.2% of the participants had a malignant lesion, whereas altogether 1.5% of the individuals were diagnosed with lung cancer. • The overall positive predictive value of the positive tests in the HUNCHEST screening program was 31.6%.

Development of a Prognostic Nomogram for Patients with Lung Adenocarcinoma in the Stages I, II, and III Based on Immune Scores

Background

Immunotherapy has significantly changed the treatment prospects of non-small cell lung cancer (NSCLC). However, there is no report based on immune score to predict the overall survival (OS) of lung adenocarcinoma (LUAD) in the stages I, II, and III. Therefore, this study aimed to investigate the immune score and the prognosis-related factors of LUAD and construct a nomogram to predict the prognosis.

Methods

A total of 390 cases with lung adenocarcinoma in the stages I, II, and III were included in the study. The clinicopathological characteristics and immune scores of LUAD patients were downloaded from the TCGA database. Cox proportional hazards regression model was used to estimate hazard ratio (HR) and 95% confidence interval (CI). A Nomogram was composed of the Cox model and internally validated using 1000 bootstrap. The concordance index (c-index) and the calibration curves were used to evaluate the model. The decision curve analysis (DCA) was performed to evaluate the clinical practical value of the model.

Results

According to the immune score, the patients were divided into low-, medium-, and high-score groups. This study showed that compared with patients with low and medium immune scores, only patients with high immune scores had significantly improved OS (HR and 95% confidence interval (CI): 0.489 [0.324‐0.737]). The C‐index for OS prediction was 0.691 (95% CI, 0.646‐0.736). The calibration curves for nomogram-predicted probabilities of 3- and 5-year survival have good ability for the calibration and discrimination.

Conclusion

The high immune score was significantly correlated with better OS of patients with LUAD in the stages I, II, and III. Moreover, the nomogram of predicting prognosis may help assess the survival of LUAD patients.

TSLP and TSLP receptors variants are associated with smoking

Background

To search for new prevention markers for early detection of the diseases caused by tobacco, we aimed to investigate the polymorphisms in TSLP and TSLPRs associated with cigarette smoking in the Saudi population.

Materials and methods

Samples were collected from 177 smokers and 126 healthy controls. Three TSLP SNPs [rs3806933, rs2289276, and rs10043985], three TSLPR SNPs [rs36133495, rs36177645, and rs36139698], and two IL7R SNPs rs1053496 and rs12516866 were analyzed by genotyping.

Results

Two TSLP SNPs (rs10043985 and rs3806933) and one TSLPR SNP (rs36139698) showed significant correlations with smoking behavior, but not IL7R rs12516866 and rs1053496. rs10043985 showed a clear association with long‐term smoking regardless of daily cigarette consumption. rs2289276 was associated with short‐term smoking but not with daily cigarette consumption. rs3806933 was highly associated with different smoker subgroups. Rs36139698 was highly associated with long‐term smokers who consumed ≥20 cigarettes/day, and the “T” allele was associated only with individuals who smoked ≤20 cigarettes/day. Rs36139698 corresponds to a P195L substitution and produces a TSLPR mutant with a predicted ΔΔG increase of 2.15 kcal/mol and has a more stable structure than the wild‐type variant.

Conclusions

Investigating TSLP and TSLPR polymorphisms is crucial for elucidating the mechanisms underlying tobacco‐induced diseases.

The plasma glutamate concentration as a complementary tool to differentiate benign PET-positive lung lesions from lung cancer

Background

Pulmonary imaging often identifies suspicious abnormalities resulting in supplementary diagnostic procedures. This study aims to investigate whether the metabolic fingerprint of plasma allows to discriminate between patients with lung inflammation and patients with lung cancer.

Methods

Metabolic profiles of plasma from 347 controls, 269 cancer patients and 108 patients with inflammation were obtained by ¹H-NMR spectroscopy. Models to discriminate between groups were trained by PLS-LDA. A test set was used for independent validation. A ROC curve was built to evaluate the diagnostic performance of potential biomarkers.

Results

Sensitivity, specificity, PPV and NPV of PET-CT to diagnose cancer are 96, 23, 76 and 71%. Metabolic profiles differentiate between cancer and inflammation with a sensitivity of 89%, a specificity of 87% and a MCE of 12%. Removal of the glutamate metabolite results in an increase of MCE (38%) and a decrease of both sensitivity and specificity (62%), demonstrating the importance of glutamate for discrimination. At the cut-off point 0.31 on the ROC curve, the relative glutamate concentration discriminates between cancer and inflammation with a sensitivity of 85%, a specificity of 81%, and an AUC of 0.88. PPV and NPV are 92 and 69%. In PET-positive patients with a relative glutamate level ≤ 0.31 the sensitivity to diagnose cancer reaches 100% with a PPV of 94%. In PET-negative patients, a relative glutamate level > 0.31 increases the specificity of PET from 23% to 58% and results in a high NPV of 100%. In case of discrepancy between SUV_max and the glutamate concentration, lung cancer is missed in 19% of the cases.

Conclusion

This study indicates that the ¹H-NMR-derived relative plasma concentration of glutamate allows discrimination between lung cancer and lung inflammation. A glutamate level ≤ 0.31 in PET-positive patients corresponds to the diagnosis of lung cancer with a higher specificity and PPV than PET-CT. Glutamate levels > 0.31 in patients with PET negative lung lesions is likely to correspond with inflammation. Caution is needed for patients with conflicting SUV_max values and glutamate concentrations. Confirmation is needed in a prospective study with external validation and by another analytical technique such as HPLC-MS.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4755-1) contains supplementary material, which is available to authorized users.

DKK4-knockdown enhances chemosensitivity of A549/DTX cells to docetaxel

Drug resistance greatly limits docetaxel efficiency in the treatment of non-small cell lung cancer (NSCLC). Dickkopf 4 (DKK4), a negative regulator of Wnt/β-catenin pathway, is believed to be involved in various human cancers; whereas the association of DKK4 with acquired docetaxel resistance in NSCLC remains unclear. In the present study, we investigated the involvement of DKK4 in the docetaxel-resistant human lung adenocarcinoma A549 (A549/DTX) cells. Our results showed that DKK4 expression was significantly increased in the A549/DTX cells compared with in the A549 cells, as well as in the culture supernatant of A549/DTX cells. DKK4 overexpression increased the resistance of A549 cells to docetaxel. DKK4-knockdown promoted inhibition of A549/DTX cell growth, and reduced the colony formation and invasion capacity of A549/DTX cells. Moreover, DKK4-knockdown promoted the pro-apoptotic effect of docetaxel characterized with caspase 3 activation and inhibition of BCL-2 expression in A549/DTX cells, which was possibly mediated by inducing the activation of c-Jun N-terminal kinase (JNK)-related signaling pathway. Thus, our results indicated that DKK4-knockdown promoted the cytotoxic and pro-apoptotic activity of A549/DTX cells, which suggests a critical role of DKK4 in docetaxel resistance of the A549 cells and provides the potential to combine docetaxel therapy with DKK4 depletion in treating NSCLC.

Lung Cancer Screening Update

Since the release of the US Preventive Services Task Force and Centers for Medicare and Medicaid Services recommendations for lung cancer screening, low-dose chest computed tomography screening has moved from the research arena to clinical practice. Lung cancer screening programs must reach beyond image acquisition and interpretation and engage in a multidisciplinary effort of clinical shared decision-making, standardization of imaging and nodule management, smoking cessation, and patient follow-up. Standardization of radiologic reports and nodule management will systematize patient care, provide quality assurance, further reduce harm, and contain health care costs. Although the National Lung Screening Trial results and eligibility criteria of a heavy smoking history are the foundation for the standard guidelines for low-dose chest computed tomography screening in the United States, currently only 27% of patients diagnosed with lung cancer would meet US lung cancer screening recommendations. Current and future efforts must be directed to better delineate those patients who would most benefit from screening and to ensure that the benefits of screening reach all socioeconomic strata and racial and ethnic minorities. Further optimization of lung cancer screening program design and patient eligibility will assure that lung cancer screening benefits will outweigh the potential risks to our patients.

Two SNPs in the promoter region of Toll-like receptor 4 gene are not associated with smoking in Saudi Arabia

Defects in the innate immune system, particularly in Toll-like receptors (TLRs), have been reported in several cigarette smoke-promoted diseases. The aim of this study was to examine the impact of tobacco smoke on allelic frequencies of TLR4 single-nucleotide polymorphisms (SNPs) and to compare the genotypic distribution of these SNPs in a Saudi Arabian population with that in previously studied populations. DNA was extracted from 303 saliva samples collected from smokers and nonsmokers. Two transitional SNPs in the promoter region of TLR4 were selected, rs2770150 (T/C) and rs10759931 (G/A). Genotype frequencies were determined using quantitative polymerase chain reaction. Our results showed a slight effect of smoking on the distribution of rs2770150 and rs10759931. However, the differences were not significant. Thus, we conclude that the SNPs selected for this study were independent of smoking and may not be related to smoking-induced diseases.

Effect of smoking on the genetic makeup of toll-like receptors 2 and 6

Background

Cigarette smoking is a major risk factor for lung cancer, asthma, and oral cancer, and is central to the altered innate immune responsiveness to infection. Many hypotheses have provided evidence that cigarette smoking induces more genetic changes in genes involved in the development of many cigarette-related diseases. This alteration may be from single-nucleotide polymorphisms (SNPs) in innate immunity genes, especially the toll-like receptors (TLRs).

Objective

In this study, the genotype frequencies of TLR2 and TLR6 in smoking and nonsmoking population were examined.

Methods

Saliva samples were collected from 177 smokers and 126 nonsmokers. The SNPs used were rs3804100 (1350 T/C, Ser450Ser) and rs3804099 (597 T/C, Asn199Asn) for TLR2 and rs3796508 (979 G/A, Val327Met) and rs5743810 (745 T/C, Ser249Pro) for TLR6.

Results

Results showed that TLR2 rs3804100 has a significant effect in short-term smokers (OR =2.63; P=0.04), and this effect is not observed in long-term smokers (>5 years of smoking). Therefore, this early mutation may be repaired by the DNA repair system. For TLR2 rs3804099, the variation in genotype frequencies between the smokers and control patients was due to a late mutation, and its protective role appears only in long-term smokers (OR =0.40, P=0.018). In TLR6 rs5743810, the TT genotype is significantly higher in smokers than in nonsmokers (OR =6.90). The effect of this SNP is observed in long-term smokers, regardless of the smoking regime per day.

Conclusion

TLR2 (rs3804100 and rs3804099) and TLR6 (rs5743810) can be used as a potential index in the diagnosis and prevention of more diseases caused by smoking.

FoxM1 inhibition enhances chemosensitivity of docetaxel-resistant A549 cells to docetaxel via activation of JNK/mitochondrial pathway

Docetaxel is recommended as a second-line chemotherapy agent for the non-small-cell lung cancer (NSCLC); however, drug resistance greatly limits its efficiency. Forkhead box M1 (FoxM1), an oncogenic transcription factor, is believed to be involved in the chemoresistance of various human cancers; whereas the association of FoxM1 with acquired docetaxel-resistance in NSCLC remains unclear. In the present study, we investigated the involvement of FoxM1 in the docetaxel-resistant human lung adenocarcinoma A549 cells (A549/DTX). Our results showed that FoxM1 expression was significantly increased in the A549/DTX cells compared with that in the parental A549 cells. FoxM1 siRNA silencing promoted the cytotoxic and pro-apoptotic effect of docetaxel in A549/DTX cells, which was possibly mediated through inducing the activation of c-Jun N-terminal kinases/mitochondrial signaling pathway. Our results suggest a critical role of FoxM1 in docetaxel-resistance of the A549 cells and form the basis for the development of combined therapy of docetaxel and FoxM1 depletion in treating NSCLC.

DNA methylation analysis of cancer-related genes in oral epithelial cells of healthy smokers

AIM

The aim of this study was to investigate the smoking habit influence on DNA methylation status in the promoters of the cancer related-genes MLH1, hTERT and TP53 in oral epithelial cells of healthy subjects.

MATERIALS AND METHODS

DNA methylation analysis was performed using methylation-sensitive restriction enzymes (MSRE) in oral epithelial cells from non-smokers, smokers and ex-smokers.

RESULTS

The investigated CpG dinucleotides located at HhaI and HpaII sites in the MLH1 gene promoter were observed to be fully methylated in the majority of DNA samples from the smoker group and statistical differences were found between non-smokers and smokers and between smokers and ex-smokers (p<0.05). The same was observed in the hTERT gene promoter at HhaI sites (p<0.05) and for HpaII sites the unmethylated condition was more frequent in smokers in comparison to non-smokers (p<0.05). For TP53, no differences were found among groups (p>0.05), with the fully methylated condition found to be a common event in healthy oral epithelial cells.

CONCLUSION

We conclude that smoking may induce changes in DNA methylation status in cancer-related genes of oral epithelial cells and that the cessation of smoking is capable of reversing this process. Based on our data, we suggest that DNA methylation status of the hTERT and MLH1 gene promoters are promising markers for screening a set of smoking-related alterations in oral cells.

Meta-analysis to assess the efficacy and toxicity of docetaxel-based doublet compared with docetaxel alone for patients with advanced NSCLC who failed first-line treatment

PURPOSE

The benefit of docetaxel-based therapy in the second-line treatment of advanced non-small cell lung cancer (NSCLC) is still unclear. The goal of this meta-analysis was to assess the efficacy and toxicity of docetaxel-based doublet compared with docetaxel alone for patients with advanced NSCLC who failed to improve with first-line treatment.

METHODS

Several databases were searched, including PubMed, Embase, and the Cochrane databases. The end points were overall survival, progression-free survival (PFS), objective response rate, disease control rate, and grade 3 or 4 adverse events. Data were extracted from the studies by 2 independent reviewers. The meta-analysis was performed by using Review Manager version 5.2. The pooled hazard ratio (HR) or odds ratio (OR) and 95% CIs were calculated by using fixed or random effects models depending on the heterogeneity of the included trials.

FINDINGS

Twelve eligible trials involving 2680 patients were identified. The intention-to-treatment analysis found that docetaxel-based therapy significantly improved overall survival (HR, 0.89 [95% CI, 0.83-0.96]; P < 0.01), PFS (HR, 0.79 [95% CI, 0.71-0.89]; P < 0.01), objective response rate (OR, 1.73 [95% CI, 1.37-2.18; P < 0.01), and disease control rate (OR, 1.30 [95% CI, 1.09-1.55]; P < 0.01). In addition, a subgroup analysis based on type of combined drug showed that there were significant improvement in PFS and overall survival in combining docetaxel with targeted therapy. In addition, a higher incidence of grade 3 or 4 diarrhea and thrombocytopenia was observed in docetaxel-based doublet therapy.

IMPLICATIONS

Based on the available evidence, docetaxel-based doublet therapy seems superior to docetaxel monotherapy as a second-line treatment for advanced NSCLC. More studies should focus on combining docetaxel with targeted therapy to identify patients who will most likely benefit from the appropriate combination targeted therapy.

Opportunities to address lung cancer disparities among African Americans

Race and socioeconomic status are well known to influence lung cancer incidence and mortality patterns in the U.S. Lung cancer incidence and mortality rates are higher among blacks than whites. In this article we review opportunities to address disparities in lung cancer incidence, mortality, and survivorship among African Americans. First, we summarize recent advances in the early detection and treatment of lung cancer. Then we consider black-white disparities in lung cancer treatment including factors that may contribute to such disparities; the literature on smoking cessation interventions for patients with or without a lung cancer diagnosis; and the important roles played by cultural competency, patient trust in their physician, and health literacy in addressing lung cancer disparities, including the need for culturally competent lung cancer patient navigators. Intervention efforts should focus on providing appropriate quality treatment for lung cancer and educating African Americans about the value of having these treatments in order to reduce these disparities. Culturally competent, patient navigation programs are needed that support lung cancer patients, especially socioeconomically disadvantaged patients, from the point of diagnosis to the initiation and completion of treatment, including cancer staging.