A randomized study of lung cancer screening with spiral computed tomography: three-year results from the DANTE trial

Low-dose computed tomography for lung cancer screening in high-risk populations: a systematic review and economic evaluation

BACKGROUND

Diagnosis of lung cancer frequently occurs in its later stages. Low-dose computed tomography (LDCT) could detect lung cancer early.

OBJECTIVES

To estimate the clinical effectiveness and cost-effectiveness of LDCT lung cancer screening in high-risk populations.

DATA SOURCES

Bibliographic sources included MEDLINE, EMBASE, Web of Science and The Cochrane Library.

METHODS

Clinical effectiveness - a systematic review of randomised controlled trials (RCTs) comparing LDCT screening programmes with usual care (no screening) or other imaging screening programmes [such as chest X-ray (CXR)] was conducted. Bibliographic sources included MEDLINE, EMBASE, Web of Science and The Cochrane Library. Meta-analyses, including network meta-analyses, were performed. Cost-effectiveness - an independent economic model employing discrete event simulation and using a natural history model calibrated to results from a large RCT was developed. There were 12 different population eligibility criteria and four intervention frequencies [(1) single screen, (2) triple screen, (3) annual screening and (4) biennial screening] and a no-screening control arm.

RESULTS

Clinical effectiveness - 12 RCTs were included, four of which currently contribute evidence on mortality. Meta-analysis of these demonstrated that LDCT, with ≤ 9.80 years of follow-up, was associated with a non-statistically significant decrease in lung cancer mortality (pooled relative risk 0.94, 95% confidence interval 0.74 to 1.19). The findings also showed that LDCT screening demonstrated a non-statistically significant increase in all-cause mortality. Given the considerable heterogeneity detected between studies for both outcomes, the results should be treated with caution. Network meta-analysis, including six RCTs, was performed to assess the relative clinical effectiveness of LDCT, CXR and usual care. The results showed that LDCT was ranked as the best screening strategy in terms of lung cancer mortality reduction. CXR had a 99.7% probability of being the worst intervention and usual care was ranked second. Cost-effectiveness - screening programmes are predicted to be more effective than no screening, reduce lung cancer mortality and result in more lung cancer diagnoses. Screening programmes also increase costs. Screening for lung cancer is unlikely to be cost-effective at a threshold of £20,000/quality-adjusted life-year (QALY), but may be cost-effective at a threshold of £30,000/QALY. The incremental cost-effectiveness ratio for a single screen in smokers aged 60-75 years with at least a 3% risk of lung cancer is £28,169 per QALY. Sensitivity and scenario analyses were conducted. Screening was only cost-effective at a threshold of £20,000/QALY in only a minority of analyses.

LIMITATIONS

Clinical effectiveness - the largest of the included RCTs compared LDCT with CXR screening rather than no screening. Cost-effectiveness - a representative cost to the NHS of lung cancer has not been recently estimated according to key variables such as stage at diagnosis. Certain costs associated with running a screening programme have not been included.

CONCLUSIONS

LDCT screening may be clinically effective in reducing lung cancer mortality, but there is considerable uncertainty. There is evidence that a single round of screening could be considered cost-effective at conventional thresholds, but there is significant uncertainty about the effect on costs and the magnitude of benefits.

FUTURE WORK

Clinical effectiveness and cost-effectiveness estimates should be updated with the anticipated results from several ongoing RCTs [particularly the NEderlands Leuvens Longkanker Screenings ONderzoek (NELSON) screening trial].

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016048530.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Donnelly EF, Kazerooni EA, Lee E, Henry TS, Boiselle PM, Crabtree TD, Iannettoni MD, Johnson GB, Laroia AT, Maldonado F, Olsen KM, Shim K, Sirajuddin A, Wu CC, Kanne JP. ACR Appropriateness Criteria® Lung Cancer Screening

Lung cancer remains the leading cause of cancer death in both men and women. Smoking is the single greatest risk factor for the development of lung cancer. For patients between the age of 55 and 80 with 30 or more pack years smoking history who currently smoke or who have quit within the last 15 years should undergo lung cancer screening with low-dose CT. In patients who do not meet these criteria but who have additional risk factors for lung cancer, lung cancer screening with low-dose CT is controversial but may be appropriate. Imaging is not recommended for lung cancer screening of patient younger than 50 years of age or patients older than 80 years of age or patients of any age with less than 20 packs per year history of smoking and no additional risk factor (ie, radon exposure, occupational exposure, cancer history, family history of lung cancer, history of COPD, or history of pulmonary fibrosis). The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Validation of lesion simulations in clinical CT data for anonymized chest and abdominal CT databases

PURPOSE

To make available to the medical imaging community a computed tomography (CT) image database composed of hybrid datasets (patient CT images with digitally inserted anthropomorphic lesions) where lesion ground truth is known a priori. It is envisioned that such a dataset could be a resource for the assessment of CT image quality, machine learning, and imaging technologies [e.g., computer aided detection (CAD) and segmentation algorithms].

ACQUISITION AND VALIDATION METHODS

This HIPPA compliant, IRB waiver of approval study consisted of utilizing 120 chest and 100 abdominal clinically acquired adult CT exams. One image series per patient exam was utilized based on coverage of the anatomical region of interest (either the thorax or abdomen). All image series were de-identified. Simulated lesions were derived from a library of anatomically informed digital lesions (93 lung and 50 liver lesions) where six and four digital lesions with nominal diameters ranging from 4 to 20 mm were inserted into lung and liver image series, respectively. Locations for lesion insertion were randomly chosen. A previously validated lesion simulation and virtual insertion technique were utilized. The resulting hybrid images were reviewed by three experienced radiologists to assure similarity with routine clinical imaging in a diverse adult population.

DATA FORMAT AND USAGE NOTES

The database is composed of four datasets that contain 100 patient cases each, for a total of 400 image series accompanied by Matlab.mat tables that provide descriptive information about the virtually inserted lesions (i.e., size, shape, opacity, and insertion location in physical (world) coordinates and voxel indices). All image and metadata are stored in DICOM format on the Quantitative Imaging Data Warehouse (https://qidw.rsna.org/#collection/57d463471cac0a4ec8ff8f46/folder/5b23dceb1cac0a4ec800a770?dialog=login), in two sets: (a) QIBA CT Hybrid Dataset I which contains Lung I and Liver I datasets, and (b) QIBA CT Hybrid Dataset II which contains Lung II and Liver II datasets. The QIDW is supported by the Radiological Society of North America (RSNA). Registration is required upon initial log in.

POTENTIAL APPLICATIONS

By simulating lesion opacity (full solid, part solid and ground glass), size, and texture, the relationship between lesion morphology and segmentation or CAD algorithm performance can be investigated without the need for repetitive patient exams. This database can also serve as a reference standard for device and reader performance studies.

Do we know enough about the effect of low-dose computed tomography screening for lung cancer on survival to act? A systematic review, meta-analysis and network meta-analysis of randomised controlled trials

BACKGROUND

Diagnosis of lung cancer frequently occurs in its later stages. Low-dose computed tomography (LDCT) could detect lung cancer early.

METHODS

Our objective was to estimate the effect of LDCT lung cancer screening on mortality in high-risk populations. A systematic review of randomised controlled trials (RCTs) comparing LDCT screening programmes with usual care (no screening) or other imaging screening programme (such as chest X-ray (CXR)) was conducted. RCTs of CXR screening were additionally included in the network meta-analysis. Bibliographic sources including MEDLINE, Embase, Web of Science and the Cochrane Library were searched to January 2017. All key review steps were done by two persons. Quality assessment used the Cochrane Risk of Bias tool. Meta-analyses were performed.

RESULTS

Four RCTs were included. More will provide data in the future. Meta-analysis demonstrated that LDCT screening with up to 9.80 years of follow-up was associated with a statistically non-significant decrease in lung cancer mortality (pooled relative risk (RR) 0.94, 95% confidence interval (CI) 0.74 to 1.19; p = 0.62). There was a statistically non-significant increase in all-cause mortality. Given the considerable heterogeneity for both outcomes, the results should be treated with caution.Network meta-analysis including the four original RCTs plus two further RCTs assessed the relative effectiveness of LDCT, CXR and usual care. The results showed that in terms of lung cancer mortality reduction LDCT was ranked as the best screening strategy, CXR screening as the worst strategy and usual care intermediate.

CONCLUSIONS

LDCT screening may be effective in reducing lung cancer mortality but there is considerable uncertainty: the largest of the RCTs compared LDCT with CXR screening rather than no screening; there is imprecision of the estimates; and there is important heterogeneity between the included study results. The uncertainty about the effect on all-cause mortality is even greater. Maturing trials may resolve the uncertainty.

Role of Low-Dose Computerized Tomography in Lung Cancer Screening among Never-Smokers

INTRODUCTION

The incidence of lung cancer among never-smokers has been increasing rapidly. The U. S. National Lung Screening Trial and the NELSON trial showed that screening using low-dose computerized tomography (LDCT) effectively reduced lung cancer mortality among heavy smokers. However, its effectiveness in never-smokers has not been well investigated. This study investigated the role of LDCT in lung cancer screening among never-smokers.

METHODS

The study was designed as a single-center, retrospective cohort study. We analyzed the data on patients who underwent LDCT screening between May 2003 and June 2016. Nodules detected by computerized tomography were classified according to the Lung Imaging Reporting and Data System criteria. The detection rate and lung cancer outcomes (type of cancer, staging of lung cancer, and mortality) according to smoking history were determined.

RESULTS

Of the 28,807 enrolled patients, 12,176 were never-smokers; of these patients, 7744 (63.6%) were women and 1218 (10.0%) were found to have lung nodules. Overall, lung cancer was diagnosed in 55 never-smokers (0.45%). In contrast, lung cancer was diagnosed in 143 (0.86%) of the 16,631 ever-smokers. Of the never-smokers with lung cancer, 51 (92.7%) presented with stage I disease, and all patients had adenocarcinomas.

CONCLUSIONS

In the never-smoker population, LDCT screening helped to detect a significant number of lung cancers. Most of these lung cancers were detected at a very early stage. The positive results of the National Lung Screening Trial in the United States and the NELSON trial may have established the value of LDCT screening for heavy smokers, but future research should consider the value of using LDCT screening in the never-smoker population.

A multi-parameterized artificial neural network for lung cancer risk prediction

The objective of this study is to train and validate a multi-parameterized artificial neural network (ANN) based on personal health information to predict lung cancer risk with high sensitivity and specificity. The 1997-2015 National Health Interview Survey adult data was used to train and validate our ANN, with inputs: gender, age, BMI, diabetes, smoking status, emphysema, asthma, race, Hispanic ethnicity, hypertension, heart diseases, vigorous exercise habits, and history of stroke. We identified 648 cancer and 488,418 non-cancer cases. For the training set the sensitivity was 79.8% (95% CI, 75.9%-83.6%), specificity was 79.9% (79.8%-80.1%), and AUC was 0.86 (0.85-0.88). For the validation set sensitivity was 75.3% (68.9%-81.6%), specificity was 80.6% (80.3%-80.8%), and AUC was 0.86 (0.84-0.89). Our results indicate that the use of an ANN based on personal health information gives high specificity and modest sensitivity for lung cancer detection, offering a cost-effective and non-invasive clinical tool for risk stratification.

Challenges in Lung Cancer Screening in Latin America

Lung cancer is the deadliest cancer worldwide and is of particular concern for Latin America. Its rising incidence in this area of the world poses myriad challenges for the region's economies, which are already struggling with limited resources to meet the health care needs of low- and middle-income populations. In this environment, we are concerned that regional governments are relatively unaware of the pressing need to implement effective strategies for the near future. Low-dose chest computed tomography (LDCT) for screening, and routine use of minimally invasive techniques for diagnosis and staging remain uncommon. According to results of the National Lung Screening Trial, LDCT lung cancer screening provided a 20% relative reduction in mortality rates among at-risk individuals. Nevertheless, this issue is still a matter of debate, particularly in developing countries, and it is not fully embraced in developing countries. The aim of this article is to provide an overview of what the standard of care is for lung cancer computed tomography screening around the world and to aid understanding of the challenges and potential solutions that can help with the implementation of LDCT in Latin America.

Low-dose computed tomography (LDCT) versus other cancer screenings in early diagnosis of lung cancer: A meta-analysis

BACKGROUND

Lung cancer is the leading cause of cancer mortality worldwide. It is often diagnosed at an advanced stage when treatment is no longer possible. Early population-based screening may provide an opportunity for early diagnosis and reduce mortality rates.

METHODS

Study characteristics were collected and outcome data (lung cancer diagnosis and mortality) were extracted and used for meta-analysis. Statistical analyses were performed using OpenMetaAnalyst-0.1503 software. The odds ratio (OR) and 95% confidence interval (CI) were used to assess LDCT compared to other screening methods under the random-effects model. The I2 statistic was used to assess heterogeneity.

RESULTS

Pooling data from 4 studies (64,129 patients) showed a higher incidence of diagnosed lung cancer with LDCT screening (OR = 1.86, 95% CI: 1.02-3.37), compared to other screening tools. However, no significant difference (OR = 1.13, 95% CI: 0.78-1.64) was found in lung cancer mortality between both groups.

CONCLUSIONS

Although no significant difference was found between LDCT and other control groups in terms of lung cancer mortality, this meta-analysis suggests an increased diagnosis of lung cancer with LDCT as compared with other screening modalities. This meta-analysis displays the potential but also the limitations of LDCT for early lung cancer detection.

Shared decision-making conversations and smoking cessation interventions: critical components of low-dose CT lung cancer screening programs

Lung cancer remains the world's deadliest cancer despite efforts to decrease smoking rates. Lung cancer screening (LCS) with low-dose computed tomography (LDCT) was shown to reduce lung cancer deaths by 20%. Screening with LDCT comes with potential harms including a high rate of false-positive test results, subsequent follow-up procedures, and radiation exposure. For some patients, the potential benefits associated with screening may be outweighed by the harms. The decision to screen must therefore take into consideration patients' risk of developing lung cancer, comorbidities that may prevent diagnostic procedures or curative surgery, and their values and preferences regarding the benefits and harms of screening. A process called shared decision-making (SDM) is recognized as a crucial feature of LCS. SDM is a patient-centered approach where healthcare providers provide best clinical evidence and then work together with patients to discern if the screening process aligns with the patient's values and preferences. Unfortunately, clinician SDM skills are often of poor quality which can lead to patients making uninformed decisions. Decision support tools that help patients make informed decisions and increase SDM on LCS are available. In 2015, the Centers for Medicare & Medicaid Services issued a coverage memo for LCS that contained an unprecedented requirement: an initial patient counseling and SDM visit with the use of at least one decision aid must occur for screening services to be reimbursed. This review focuses on SDM and suggests ways to increase the prevalence and effectiveness of SDM in LCS programs. Stopping smoking greatly reduces a person's risk for developing lung cancer, and smoking cessation messages in LCS guidelines from major medical organizations and interventions in LCS programs are explored. LCS has come of age; so too has SDM as it is an integral part of LCS programs.

Lung cancer screening with low-dose spiral computed tomography: evidence from a pooled analysis of two Italian randomized trials

The benefits and harms of lung cancer (LC) screening with low-dose computed tomography (LDCT) are debatable. Positive results from the US National Lung Screening Trial were not evident in the European trials, possibly due to their smaller sample sizes. To address this issue, we conducted a patient-level pooled analysis of two Italian randomized controlled trials. Data from DANTE and MILD trials were combined for a total of 3640 individuals in the LDCT arm and 2909 in the control arm. LC and overall mortality were analyzed using multivariate hazard ratios (HRs) and log-rank tests stratified by study. The median follow-up was 8.2 years, with a total of 30 480 person-years in the LDCT arm and 22 157 in the control arm. A total of 192 patients developed LC in the LDCT arm and 105 in the control arm. Half of the LC cases in the LDCT arm had stage IA or IB cancer, as compared with 21% in the control arm. Overall mortality rates/100 000 person-years were 925 in the LDCT arm and 1074 in the control arm, and LC mortality rates were 299 and 357, respectively. The multivariate pooled overall mortality HR was 0.89 (95% confidence interval: 0.74-1.06) and the LC mortality HR was 0.83 (95% confidence interval: 0.61-1.12) for the LDCT arm as compared with the control arm. The present pooled analysis shows a nonsignificant 11% reduction in overall mortality in individuals undergoing LDCT screening as compared with the control arm. A pooled analysis of all European trials would be a useful contribution to assess the real benefit of LDCT screening.

Localized thin-section CT with radiomics feature extraction and machine learning to classify early-detected pulmonary nodules from lung cancer screening

Lung cancer screening aims to detect small pulmonary nodules and decrease the mortality rate of those affected. However, studies from large-scale clinical trials of lung cancer screening have shown that the false-positive rate is high and positive predictive value is low. To address these problems, a technical approach is greatly needed for accurate malignancy differentiation among these early-detected nodules. We studied the clinical feasibility of an additional protocol of localized thin-section CT for further assessment on recalled patients from lung cancer screening tests. Our approach of localized thin-section CT was integrated with radiomics features extraction and machine learning classification which was supervised by pathological diagnosis. Localized thin-section CT images of 122 nodules were retrospectively reviewed and 374 radiomics features were extracted. In this study, 48 nodules were benign and 74 malignant. There were nine patients with multiple nodules and four with synchronous multiple malignant nodules. Different machine learning classifiers with a stratified ten-fold cross-validation were used and repeated 100 times to evaluate classification accuracy. Of the image features extracted from the thin-section CT images, 238 (64%) were useful in differentiating between benign and malignant nodules. These useful features include CT density (p  =  0.002 518), sigma (p  =  0.002 781), uniformity (p  =  0.032 41), and entropy (p  =  0.006 685). The highest classification accuracy was 79% by the logistic classifier. The performance metrics of this logistic classification model was 0.80 for the positive predictive value, 0.36 for the false-positive rate, and 0.80 for the area under the receiver operating characteristic curve. Our approach of direct risk classification supervised by the pathological diagnosis with localized thin-section CT and radiomics feature extraction may support clinical physicians in determining truly malignant nodules and therefore reduce problems in lung cancer screening.

Screening for Lung Cancer: CHEST Guideline and Expert Panel Report

BACKGROUND

Low-dose chest CT screening for lung cancer has become a standard of care in the United States in the past few years, in large part due to the results of the National Lung Screening Trial. The benefit and harms of low-dose chest CT screening differ in both frequency and magnitude. The translation of a favorable balance of benefit and harms into practice can be difficult. Here, we update the evidence base for the benefit, harms, and implementation of low radiation dose chest CT screening. We use the updated evidence base to provide recommendations where the evidence allows, and statements based on experience and expert consensus where it does not.

METHODS

Approved panelists developed key questions using the PICO (population, intervention, comparator, and outcome) format to address the benefit and harms of low-dose CT screening, as well as key areas of program implementation. A systematic literature review was conducted by using MEDLINE via PubMed, Embase, and the Cochrane Library. Reference lists from relevant retrievals were searched, and additional papers were added. The quality of the evidence was assessed for each critical or important outcome of interest using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach. Important clinical questions were addressed based on the evidence developed from the systematic literature review. Graded recommendations and ungraded statements were drafted, voted on, and revised until consensus was reached.

RESULTS

The systematic literature review identified 59 studies that informed the response to the 12 PICO questions that were developed. Key clinical questions were addressed resulting in six graded recommendations and nine ungraded consensus based statements.

CONCLUSIONS

Evidence suggests that low-dose CT screening for lung cancer results in a favorable but tenuous balance of benefit and harms. The selection of screen-eligible patients, the quality of imaging and image interpretation, the management of screen-detected findings, and the effectiveness of smoking cessation interventions can affect this balance. Additional research is needed to optimize the approach to low-dose CT screening.

Screen-detected multiple primary lung cancers in the ITALUNG trial

Occurrence of multiple primary lung cancers (MPLC) in individuals undergoing low-dose computed tomography (LDCT) screening has not been thoroughly addressed. We investigated MPLC in subjects recruited in the ITALUNG randomized clinical trial. Cases of cytologically/histologically proven MPLC detected at screening LDCT or follow-up CT were selected and pathologically re-evaluated according to the WHO 2015 classification. Overall 16 MPLC were diagnosed at screening LDCT (n=14, all present at baseline) or follow-up CT (n=2) in six subjects (4 in one subject, 3 in two and 2 in three subjects), representing 0.43% of the 1,406 screenees and 15.8% of the 38 subjects with at least one screen-detected primary lung cancer. MPLC included 9 adenocarcinomas in three subjects and a combination of 7 different tumour histotypes in three subjects. MPLC, mostly adenocarcinomas, are not uncommon in smokers and ex-smokers with at least one LDCT screen detected primary lung cancer.

Early detection of lung cancer by using an autoantibody panel in Chinese population

We have previously identified a panel of autoantibodies (AABs), including p53, GAGE7, PGP9.5, CAGE, MAGEA1, SOX2 and GBU4-5, that was helpful in the early diagnosis of lung cancer. This large-scale, multicenter study was undertaken to validate the clinical value of this 7-AABs panel for early detection of lung cancer in a Chinese population. Two independent sets of plasma samples from 2308 participants were available for the assay of AABs (training set = 300; validation set = 2008). The concentrations of AABs were quantitated by enzyme-linked immunosorbent assay (ELISA), and the optimal cutoff value for each AAB was determined in the training set and then applied in the validation set. The value of the 7-AABs panel for the early detection of lung cancer was assessed in 540 patients who presented with ground-glass nodules (GGNs) and/or solid nodules. In the validation set, the sensitivity and specificity of the 7-AABs panel were 61% and 90%, respectively. For stage I and stage II non-small cell lung cancer (NSCLC), the sensitivity of the 7-AABs panel was 62% and 59%, respectively, and for limited stage small cell lung cancer (SCLC) it was 59%; these sensitivity values were considerably higher than for traditional biomarkers (including CEA, NSE and CYFRA21-1). Importantly, the combination of the 7-AABs panel and low-dose computed tomography (CT) scanning significantly improved the diagnostic yield in patients presenting with GGNs and/or solid nodules. In conclusion, our 7-AABs panel has clinical value for early detection of lung cancer, including early-stage lung cancer presenting as GGNs.

Lung cancer screening

PURPOSE OF REVIEW

Lung cancer screening with low-dose chest computed tomography is now recommended for high-risk individuals by the US Preventive Services Task Force. This recommendation was informed by several randomized controlled trials, the largest of which, the National Lung Screening Trial, demonstrated a 20% relative reduction in lung cancer mortality with annual low-dose chest computed tomography compared with chest radiography.

RECENT FINDINGS

The benefit of lung cancer screening must be balanced against potential harms, including a high false-positive rate with consequent further evaluative studies and invasive testing. It is critical that harms be minimized as screening generalizes to the broad community. Informed decision making between providers and patients should include individualized risk assessment, a discussion of both potential benefit and harm, and tobacco treatment. Given the multiple components required for high quality, screening should ideally occur in the context of a multidisciplinary program.

SUMMARY

We are in the early days of lung cancer screening, still with much to learn. Ongoing studies are necessary to refine the definition of a positive screen and develop better methods of distinguishing between true positive and false-positive results. Novel approaches, including the development of multicomponent lung cancer biomarkers, will likely inform and improve our future screening practice.

[Lung cancer screening with thoracic X‑ray and CT : Current situation]

CLINICAL/METHODICAL ISSUE

Attempts at the early detection of lung cancer using imaging methods began as far back as the 1950s.

STANDARD RADIOLOGICAL METHODS

Several studies attempted to demonstrate a reduction of lung cancer mortality by chest radiography screening but all were unsuccessful.

METHODICAL INNOVATIONS

Even the first small screening studies using computed tomography (CT) could not demonstrate a reduction in lung cancer-specific mortality until in 2011 the results of the largest randomized controlled low-dose CT screening study in the USA (NLST) were published. The NLST results could show a significant 20 % reduction of lung cancer mortality in elderly and heavy smokers using CT.

PERFORMANCE

Confirmation of the NLST results are urgently needed so that the data of the largest European study (NELSON) are eagerly awaited.

ACHIEVEMENTS

Pooled with the data from several smaller European studies these results will provide important information and evidence for the establishment of future CT screening programs in Europe.

PRACTICAL RECOMMENDATIONS

Randomized controlled trials are the basis of evidence-based medicine; therefore, the positive results of the methodologically very good NLST study cannot be ignored, even if it is the only such study completed so far with highly convincing conclusions. The NLST results clearly demonstrate that positive effects for the health of the population can only be expected if the processes are clearly defined and the quality is assured.

Implementation of lung cancer CT screening in the Nordic countries

INTRODUCTION

We review the current knowledge of CT screening for lung cancer and present an expert-based, joint protocol for the proper implementation of screening in the Nordic countries.

MATERIALS AND METHODS

Experts representing all the Nordic countries performed literature review and concensus for a joint protocol for lung cancer screening.

RESULTS AND DISCUSSION

Areas of concern and caution are presented and discussed. We suggest to perform CT screening pilot studies in the Nordic countries in order to gain experience and develop specific and safe protocols for the implementation of such a program.

Exhaled breath condensate biomarkers for the early diagnosis of lung cancer using proteomics

We explored whether the proteomic analysis of exhaled breath condensate (EBC) may provide biomarkers for noninvasive screening for the early detection of lung cancer (LC). EBC was collected from 192 individuals [49 control (C), 49 risk factor-smoking (S), 46 chronic obstructive pulmonary disease (COPD) and 48 LC]. With the use of liquid chromatography and tandem mass spectrometry, 348 different proteins with a different pattern among the four groups were identified in EBC samples. Significantly more proteins were identified in the EBC from LC compared with other groups (C: 12.4 ± 1.3; S: 15.3 ± 1; COPD: 14 ± 1.6; LC: 24.2 ± 3.6; P = 0.0001). Furthermore, the average number of proteins identified per sample was significantly higher in LC patients, and receiver operating characteristic curve (ROC) analysis showed an area under the curve of 0.8, indicating diagnostic value. Proteins frequently detected in EBC, such as dermcidin and hornerin, along with others much less frequently detected, such as hemoglobin and histones, were identified. Cytokeratins (KRTs) were the most abundant proteins in EBC samples, and levels of KRT6A, KRT6B, and KRT6C isoforms were significantly higher in samples from LC patients ( P = 0.0031, 0.0011, and 0.0009, respectively). Moreover, the amount of most KRTs in EBC samples from LC patients showed a significant positive correlation with tumor size. Finally, we used a random forest algorithm to generate a robust model using EBC protein data for the diagnosis of patients with LC where the area under the ROC curve obtained indicated a good classification (82%). Thus this study demonstrates that the proteomic analysis of EBC samples is an appropriated approach to develop biomarkers for the diagnosis of lung cancer.

Incidental lung cancers and positive computed tomography images in people living with HIV

OBJECTIVE

Lung cancer screening with low-dose computed tomography (LDCT) of high-risk groups in the general population is recommended by several authorities. This may not be feasible in people living with HIV (PLWHIV) due to higher prevalence of nodules. We therefore assessed the prevalence of positive computed tomography (CT) images and lung cancers in PLWHIV.

DESIGN

The Copenhagen comorbidity in HIV infection (COCOMO) study is an observational, longitudinal cohort study. Single-round LDCT was performed with subsequent clinical follow-up (NCT02382822).

METHOD

Outcomes included histology-proven lung cancer identified by LDCT and positive CT images (noncalcified nodules) in the entire cohort and in the high-risk group (>50 years of age and >30 pack-years). We also assessed the procedures and adverse events, and clinical factors associated with a positive CT image.

RESULTS

LDCT was performed in 901 patients, including 113 at high risk for lung cancer. A positive image was found in 28 (3.1% of the entire cohort and 9.7% of the high-risk group). Nine patients (all in the high-risk group) had invasive procedures undertaken with no serious adverse events. Lung cancer (stages IA, IIA, and IIIA) was diagnosed in three patients from the high-risk group (2.7%). CD4 cell count less than 500 cells/μl and CD4 nadir less than 200 cells/μl were each independently associated with increased odds of a positive image odds ratio 2.32 [95% confidence interval: 1.01-5.13, P = 0.04] and odds ratio 2.63 [95% confidence interval: 1.13-6.66, P = 0.03].

CONCLUSION

Randomized LDCT screening trials in PLWHIV are nonexistent, but these findings are comparable with screening rounds from the general population in terms of prevalence of lung cancer and positive CT images.

Progress and prospects of early detection in lung cancer

Lung cancer is the leading cause of cancer-related death in the world. It is broadly divided into small cell (SCLC, approx. 15% cases) and non-small cell lung cancer (NSCLC, approx. 85% cases). The main histological subtypes of NSCLC are adenocarcinoma and squamous cell carcinoma, with the presence of specific DNA mutations allowing further molecular stratification. If identified at an early stage, surgical resection of NSCLC offers a favourable prognosis, with published case series reporting 5-year survival rates of up to 70% for small, localized tumours (stage I). However, most patients (approx. 75%) have advanced disease at the time of diagnosis (stage III/IV) and despite significant developments in the oncological management of late stage lung cancer over recent years, survival remains poor. In 2014, the UK Office for National Statistics reported that patients diagnosed with distant metastatic disease (stage IV) had a 1-year survival rate of just 15-19% compared with 81-85% for stage I.

[Lung Nodules Assessment--Analysis of Four Guidelines]

近20年来，随着计算机断层扫描（computed tomography, CT）技术的提高和肺癌高危人群筛查的普及，越来越多的肺部小结节被发现，然而肺结节的定性诊断仍有很多困难。肺结节是临床上一种常见的现象，恶性结节早期发病比较隐匿，如果不进行早期干预，其病程迅速、恶性程度强、预后差。如果能在早期阶段对病灶进行手术切除，将会明显改善肺癌患者的预后。目前针对肺结节的处理指南层出不穷，但各大指南均未达成统一的共识。本文拟对在国内影响最大的四个指南：美国国家综合癌症网络非小细胞肺癌（non-small cell lung cancer, NSCLC）临床实践指南、美国胸科医师协会肺癌诊疗指南、Fleischner-Society肺结节处理策略指南、肺结节的评估亚洲共识指南所推荐的肺结节诊断和处理策略进行介绍和分析。

Mortality outcomes of low-dose computed tomography screening for lung cancer in urban China: a decision analysis and implications for practice

BACKGROUND

Mortality outcomes in trials of low-dose computed tomography (CT) screening for lung cancer are inconsistent. This study aimed to evaluate whether CT screening in urban areas of China could reduce lung cancer mortality and to investigate the factors that associate with the screening effect.

METHODS

A decision tree model with three scenarios (low-dose CT screening, chest X-ray screening, and no screening) was developed to compare screening results in a simulated Chinese urban cohort (100,000 smokers aged 45-80 years). Data of participant characteristics were obtained from national registries and epidemiological surveys for estimating lung cancer prevalence. The selection of other tree variables such as sensitivities and specificities of low-dose CT and chest X-ray screening were based on literature research. Differences in lung cancer mortality (primary outcome), false diagnoses, and deaths due to false diagnosis were calculated. Sensitivity analyses were performed to identify the factors that associate with the screening results and to ascertain worst and optimal screening effects considering possible ranges of the variables.

RESULTS

Among the 100,000 subjects, there were 448, 541, and 591 lung cancer deaths in the low-dose CT, chest X-ray, and no screening scenarios, respectively (17.2% reduction in low-dose CT screening over chest X-ray screening and 24.2% over no screening). The costs of the two screening scenarios were 9387 and 2497 false diagnoses and 7 and 2 deaths due to false diagnosis among the 100,000 persons, respectively. The factors that most influenced death reduction with low-dose CT screening over no screening were lung cancer prevalence in the screened cohort, low-dose CT sensitivity, and proportion of early-stage cancers among low-dose CT detected lung cancers. Considering all possibilities, reduction in deaths (relative numbers) with low-dose CT screening in the worst and optimal cases were 16 (5.4%) and 288 (40.2%) over no screening, respectively.

CONCLUSIONS

In terms of mortality outcomes, our findings favor conducting low-dose CT screening in urban China. However, approaches to reducing false diagnoses and optimizing important screening conditions such as enrollment criteria for screening are highly needed.

Estimation of the tumor size at cure threshold among aggressive non-small cell lung cancers (NSCLCs): evidence from the surveillance, epidemiology, and end results (SEER) program and the national lung screening trial (NLST)

The National Lung Screening Trial (NLST) demonstrated that non-small cell lung cancer (NSCLC) mortality can be reduced by a program of annual CT screening in high-risk individuals. However, CT screening regimens and adherence vary, potentially impacting the lung cancer mortality benefit. We defined the NSCLC cure threshold as the maximum tumor size at which a given NSCLC would be curable due to early detection. We obtained data from 518,234 NSCLCs documented in the U.S. SEER cancer registry between 1988 and 2012 and 1769 NSCLCs detected in the NLST. We demonstrated mathematically that the distribution function governing the cure threshold for the most aggressive NSCLCs, G(x|Φ = 1), was embedded in the probability function governing detection of SEER-documented NSCLCs. We determined the resulting probability functions governing detection over a range of G(x|Φ = 1) scenarios and compared them with their expected functional forms. We constructed a simulation framework to determine the cure threshold models most consistent with tumor sizes and outcomes documented in SEER and the NLST. Whereas the median tumor size for lethal NSCLCs documented in SEER is 43 mm (males) and 40 mm (females), a simulation model in which the median cure threshold for the most aggressive NSCLCs is 10 mm (males) and 15 mm (females) best fit the SEER and NLST data. The majority of NSCLCs in the NLST were treated at sizes greater than our median cure threshold estimates. New technology is needed to better distinguish and treat the most aggressive NSCLCs when they are small (i.e., 5-15 mm).

Relationship between computed tomography morphology and prognosis of patients with stage I non-small cell lung cancer

This study aimed to explore the relationship between computed tomography morphology and prognosis of patients with stage I non-small cell lung cancer (NSCLC). From May 2009 to May 2011, a total of 124 patients diagnosed with stage I NSCLC were included. All patients had complete chest computed tomography scans. Five-year follow-up was conducted. Univariate and multivariate Cox regression analyses were performed to estimate the prognostic factors for patients with stage I NSCLC. The 5-year survival rate was 67.74% (84/124). The 5-year survival rates of patients with stage T1a, T1b, and T2a were 89.19%, 75.00%, and 41.86%, respectively. The 5-year survival rates of patients with homogeneity, inhomogeneity, vacuole, and cavity were 68.42%, 72.09%, 59.46%, and 83.33%, respectively. The 5-year survival rates of patients with different margin features were 83.33% (slick margin), 79.73% (lobulation sign), and 39.47% (short burr). The 5-year survival rates of patients with normal, halo, vessel convergence, bronchial transection, and vascular bundle thickening were 84.38%, 72.73%, 71.79%, 52.00%, and 47.06%, respectively. The 5-year survival rates of patients with normal and pleura thickening/indentation were 81.93% and 39.02%. Univariate analysis demonstrated that tumor node metastasis staging, tumor margin, tumor periphery, and pleural invasion were related to the prognosis of stage I NSCLC patients. Cox regression analysis confirmed that T2a stage, pleura thickening/indentation were independent risk factors for poor prognosis of stage I NSCLC. In conclusion, our findings indicate that T2a stage, pleura thickening/indentation might be prognostic factors in stage I NSCLC.

Reflections on the Implementation of Low-Dose Computed Tomography Screening in Individuals at High Risk of Lung Cancer in Spain

Lung cancer (LC) is a major public health issue. Despite recent advances in treatment, primary prevention and early diagnosis are key to reducing the incidence and mortality of this disease. A recent clinical trial demonstrated the efficacy of selective screening by low-dose computed tomography (LDCT) in reducing the risk of both lung cancer mortality and all-cause mortality in high-risk individuals. This article contains the reflections of an expert group on the use of LDCT for early diagnosis of LC in high-risk individuals, and how to evaluate its implementation in Spain. The expert group was set up by the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR), the Spanish Society of Thoracic Surgery (SECT), the Spanish Society of Radiology (SERAM) and the Spanish Society of Medical Oncology (SEOM).

[Macrophage Inhibitory Cytokine-1 (MIC-1) as A Biomarker for Diagnosis and Prognosis of Stage I-II Non-small Cell Lung Cancer]

背景与目的

巨噬细胞抑制因子-1（macrophage inhibitory cytokine-1, MIC-1）是人转化生长因子β（transforming growth factor-β, TGF-β）超家族中重要成员，研究发现MIC-1表达水平在多种上皮来源肿瘤患者血清中均有显著升高。本研究旨在探讨MIC-1在早期非小细胞肺癌（non-small cell lung cancer, NSCLC）诊断及其与临床病理特征间的关系，以及与术后复发/转移及预后的相关性。

方法

采用酶联免疫吸附试验（enzymelinked immunosorbent assay, ELISA）方法检测152例早期肺癌、48例肺良性疾病患者及105例正常对照人群血清MIC-1浓度，分析MIC-1诊断肺癌中的作用，同时分析血清MIC-1浓度与临床病理特征、复发/转移及预后的相关性。

结果

早期肺癌患者组MIC-1血清水平高于正常对照组（P < 0.001）和肺良性疾病组（P < 0.001），设1, 000 pg/mL为诊断肺癌的临界值，MIC-1检测肺癌的敏感性和特异性分别为70.4%和99.0% [曲线下面积（area under curve, AUC）: 0.90；95%CI: 0.87-0.94]；MIC-1血清水平与年龄（P=0.001）、性别（P=0.03）有关，病理TNM分期T2的患者MIC-1血清水平高于T1患者（P=0.022）；血清MIC-1 > 1, 465 pg/mL组的患者3年生存率为77.6%，低于血清MIC-1 < 1, 465 pg/mL组的患者94.8%（P=0.022），Cox回归多因素分析结果显示，血清MIC-1 > 1, 465 pg/mL是Ⅰ期、Ⅱ期NSCLC独立的预后因素（HR=3.37, 95%CI: 1.09-10.42, P=0.035）。

结论

MIC-1作为血清肿瘤生物标志物，可能有助于提高肺癌早期诊断。MIC-1的检测对判断Ⅰ期、Ⅱ期NSCLC患者预后有预测价值，可能为其独立的预后指标。

Risk stratification based on screening history: the NELSON lung cancer screening study

BACKGROUND

Debate about the optimal lung cancer screening strategy is ongoing. In this study, previous screening history of the Dutch-Belgian Lung Cancer Screening trial (NELSON) is investigated on if it predicts the screening outcome (test result and lung cancer risk) of the final screening round.

METHODS

15 792 participants were randomised (1:1) of which 7900 randomised into a screening group. CT screening took place at baseline, and after 1, 2 and 2.5 years. Initially, three screening outcomes were possible: negative, indeterminate or positive scan result. Probability for screening outcome in the fourth round was calculated for subgroups of participants.

RESULTS

Based on results of the first three rounds, three subgroups were identified: (1) those with exclusively negative results (n=3856; 73.0%); (2) those with ≥1 indeterminate result, but never a positive result (n=1342; 25.5%); and (3) with ≥1 positive result (n=81; 1.5%). Group 1 had the highest probability for having a negative scan result in round 4 (97.2% vs 94.8% and 90.1%, respectively, p<0.001), and the lowest risk for detecting lung cancer in round 4 (0.6% vs 1.6%, p=0.001). 'Smoked pack-years' and 'screening history' significantly predicted the fourth round test result. The third round results implied that the risk for detecting lung cancer (after an interval of 2.5 years) was 0.6% for those with negative results compared with 3.7% of those with indeterminate results.

CONCLUSIONS

Previous CT lung cancer screening results provides an opportunity for further risk stratifications of those who undergo lung cancer screening.

TRIAL REGISTRATION NUMBER

Results, ISRCTN63545820.

Pilot study on use of home telephoning to identify and recruit high-risk individuals for lung cancer screening

Widespread lung cancer screening with low-dose computed tomography is urgently needed in Europe to identify lung cancers early and reduce lung cancer deaths. The most effective method of identifying high-risk individuals and recruiting them for screening has not been determined. In the present pilot study we investigated direct telephoning to families as a way of identifying high risk individuals and recruiting them to a screening/smoking cessation program, that avoided the selection bias of voluntary screening. Families in the province of Milan, Italy, were contacted by telephone at their homes and asked about family members over 50 years who were heavy smokers (30 or more pack-years). Persons meeting these criteria were contacted and asked to participate in the program. Those who agreed were given an appointment to undergo screening and receive smoking cessation counseling. Among the 1000 contacted families, involving 2300 persons, 44 (1.9%) were eligible for LDCT screening, and 12 (27%) of these participated in the program. The cost of this recruitment strategy pilot study was around 150 euro per screened subject. We obtained useful information on the proportion of the general population eligible for lung cancer screening and the proportion of those who responded. However the cost of home telephone calling is probably too high to be practicable as a method of recruiting high risk persons for screening. Alternative recruitment methods, possibly involving family physicians practitioners, need to be investigated.

Screening for lung cancer

This review will comprise a general overview of the epidemiology of lung cancer, as well as lung cancer risk factors, screening modalities, current guideline recommendations for screening, and our approach to lung cancer screening.

Lung cancer screening with ultra-low dose CT using full iterative reconstruction

PURPOSE

To investigate the diagnostic capability of ultra-low-dose CT (ULDCT) with full iterative reconstruction (f-IR) for lung cancer screening.

MATERIALS AND METHODS

All underwent ULDCT and/or low-dose CT (LD-CT) on a 320-detector scanner. ULDCT images were reconstructed with f-IR. We qualitatively and quantitatively studied 95 nodules in 69 subjects. Two radiologists classified the nodules on ULDCT images as solid-, part-solid-, and pure ground-glass (PGG) and recorded their mean size. Their findings were compared with the reference standard. The observer performance study included 7 other radiologists and 35 subjects with- and 15 without nodules. The results were analyzed by AFROC analysis.

RESULTS

In the qualitative study, the kappa values between observers 1 and 2, respectively, and the reference standard were 0.70 and 0.83; the intra-class correlation coefficients for the nodule diameter between the reference standard and their measurements were 0.84 and 0.90. The 95% confidence interval (CI) for the area under the curve (AUC) difference for nodule detection on LDCT and ULDCT was -0.03 to 0.07. The 95% CI crossed the 0 difference in the AUC but not the pre-defined non-inferiority margin of -0.08.

CONCLUSION

The diagnostic ability of ULDCT using f-IR is comparable to LDCT.

Lung cancer screening with low-dose CT in Europe: strength and weakness of diverse independent screening trials

A North American trial reported a significant reduction of lung cancer mortality and overall mortality as a result of annual screening using low-dose computed tomography (LDCT). European trials prospectively tested a variety of possible screening strategies. The main topics of current discussion regarding the optimal screening strategy are pre-test selection of the high-risk population, interval length of LDCT rounds, definition of positive finding, and post-test apportioning of lung cancer risk based on LDCT findings. Despite the current lack of statistical evidence regarding mortality reduction, the European independent diverse strategies offer a multi-perspective view on screening complexity, with remarkable indications for improvements in cost-effectiveness and harm-benefit balance. The UKLS trial reported the advantage of a comprehensive and simple risk model for selection of patients with 5% risk of lung cancer in 5 years. Subjective risk prediction by biological sampling is under investigation. The MILD trial reported equal efficiency for biennial and annual screening rounds, with a significant reduction in the total number of LDCT examinations. The NELSON trial introduced volumetric quantification of nodules at baseline and volume-doubling time (VDT) for assessment of progression. Post-test risk refinement based on LDCT findings (qualitative or quantitative) is under investigation. Smoking cessation remains the most appropriate strategy for mortality reduction, and it must therefore remain an integral component of any lung cancer screening programme.

Lung cancer screening: detected nodules, what next?

Since the success of the NLST study, the incorporation of lung cancer screening programs into current academic programs has been growing. Center for Medicare and Medicaid Services have acknowledged the importance and potential impact of lung cancer screening by making it a reimbursable study. Based on Fleischner Society Guidelines, many nodules will require follow-up imaging. The remainder of those nodules will need tissue to appropriately make the diagnosis. The use of bronchoscopy with transbronchial biopsy has been a standard technique for many years, but as smaller nodules need to be assessed, more advanced tools, such as endobronchial ultrasound and electromagnetic navigation are now improving the yield on the diagnosis of these smaller peripheral nodules. As electromagnetic navigation and peripheral ultrasound are significant changes from practice only 10 years ago, further advancements in the technology, such as bronchoscopic robots and advanced optical imaging tools, that are becoming available, need to be assessed as to their possible incorporation into the evaluation of peripheral nodules. The ceiling to the diagnosis of these small lesions remains at 70-75%; techniques and tools need to be used to improve upon this to maximize the impact of lung cancer screening and minimize the risk to patients.

Differential diagnosis of lung cancer, its metastasis and chronic obstructive pulmonary disease based on serum Vegf, Il-8 and MMP-9

Chronic obstructive pulmonary disease (COPD) patients are at higher risk of developing lung cancer and its metastasis, but no suitable biomarker has been reported for differential diagnosis of these patients. Levels of serum biomarkers (VEGF, IL-8, MMP-9 and MMP-2) were analyzed in these patients, which were compared with healthy donors (HD). Levels of VEGF (P < 0.005) and MMP-9 (P < 0.05) were significantly higher in COPD patients than HD. Compared to HD, a decrease in IL-8 (~8.1 folds; P < 0.0001) but an increase in MMP-9 (~1.6 folds; P < 0.05) levels were observed in the lung cancer patients. Cancer patients showed significantly (P < 0.005) lower levels of serum VEGF (1.9 folds) and IL-8 (~9 folds) than the COPD patients. VEGF level was significantly higher (2.6 folds; P < 0.0005) in metastatic than non-metastatic cancer patients. However, MMP-2 didn't show significant variation in these patients. The Youden's index (YI) values for lung cancer diagnosis in HD using IL-8 was 0.55 with 83.3% overall accuracy. VEGF was able to diagnose COPD in HD with better YI (0.38) and overall accuracy (70.6%). IL-8 was able to diagnose cancer in COPD patients and HD with YI values of 0.35, 0.55 with 71% and 83.3% overall accuracy, respectively.

Efficacy of low-dose computed tomography screening for lung cancer: the current state of evidence of mortality reduction

The interim and final results of randomized controlled trials on the efficacy of lung cancer computed tomography (CT) screening have been reported recently from Western countries. The outcome of the National Lung Screening Trial (NLST) demonstrated the efficacy of low-dose thoracic CT screening for heavy smokers; however, other studies have found no apparent reduction in the mortality rate, and the outcome of the NELSON study is awaited. To date, a few studies have reported on the efficacy of lung cancer CT screening for non-/light smokers. A report from the Hitachi district, which is an ecological/time series study where non-/light smokers account for approximately half of the CT screening examinees, was published in 2012, with an outcome suggesting efficacy. Currently, a randomized controlled trial (JECS Study) is underway in Japan with non-/light smokers as the subjects, and this trial is very important in terms of cancer prevention.

[Present Situation of Lung Cancer Screening Methods]

肺癌是目前恶性肿瘤死亡的首要原因，早期诊断对肺癌的预后至关重要。研究显示低剂量计算机断层扫描（computed tomography, CT）筛查可以使肺癌的死亡率下降。但其存在的问题不可忽视，如过高的假阳性率、过度诊断、辐射效应等。作为一种肿瘤无创筛查方法，血液相关肿瘤标志物的检测，在肺癌早期诊断中显示出良好的敏感性和特异性。如何利用现有的筛查手段，建立肺癌筛查综合模式，需要更多大规模的临床研究。

Can CT Screening Give Rise to a Beneficial Stage Shift in Lung Cancer Patients? Systematic Review and Meta-Analysis

OBJECTIVES

To portray the stage characteristics of lung cancers detected in CT screenings, and explore whether there's universal stage superiority over other methods for various pathological types using available data worldwide in a meta-analysis approach.

MATERIALS AND METHODS

EMBASE and MEDLINE were searched for studies on lung cancer CT screening in natural populations through July 2015 without language or other filters. Twenty-four studies (8 trials and 16 cohorts) involving 1875 CT-detected lung cancer patients were enrolled and assessed by QUADAS-2. Pathology-confirmed stage information was carefully extracted by two reviewers. Stage I or limited stage proportions were pooled by random effect model with Freeman-Tukey double arcsine transformation.

RESULTS

Pooled stage I cancer proportion in CT screenings was 73.2% (95% confidence interval: 68.6%, 77.5%), with a significant rising trend (Ptrend<0.05) from baseline (64.7%) to ≥5 repeat rounds (87.1%). Relative to chest radiograph and usual care, the increased stage I proportions in CT were 12.2% (P>0.05), and 46.5% (P<0.05), respectively. Pathology-specifically, adenocarcinomas (66%) and squamous cell lung cancers (17%) composed the majority of CT-detected lung cancers, and had significantly higher stage I proportions relative to chest radiograph (bronchioloalveolar adenocarcinomas, 80.9% vs 51.4%; other adenocarcinomas, 58.8% vs 38.3%; squamous cell lung cancers, 52.3% vs 38.3%; all P<0.05). However, the percentage of small cell lung cancer was lower using CT than other detection routes, and no significant difference in limited stage proportion was observed (6.8% vs 10.8%, P>0.05).

CONCLUSION

CT screening can detect more early stage non-small cell lung cancers, but not all of them could be beneficial as there are a considerable number of indolent ones such as bronchioloalveolar adenocarcinomas. Still, current evidence is lacking regarding small cell lung cancers.

Macrophage Inhibitory Cytokine-1 as a Novel Diagnostic and Prognostic Biomarker in Stage I and II Nonsmall Cell Lung Cancer

BACKGROUND

Increased level of serum macrophage inhibitory cytokine-1 (MIC-1), a member of transforming growth factor-μ superfamily, was found in patients with epithelial tumors. This study aimed to evaluate whether serum level of MIC-1 can be a candidate diagnostic and prognostic indicator for early-stage nonsmall cell lung cancer (NSCLC).

METHODS

A prospective study enrolled 152 patients with Stage I-II NSCLC, who were followed up after surgical resection. Forty-eight patients with benign pulmonary disease (BPD) and 105 healthy controls were also included in the study. Serum MIC-1 levels were measured using an enzyme-linked immunosorbent assay, and the association with clinical and prognostic features was analyzed.

RESULTS

In patients with NSCLC, serum protein levels of MIC-1 were significantly increased compared with healthy controls and BPD patients (all P< 0.001). A threshold of 1000 pg/ml of MIC-1 was found in patients with early-stage (Stage I and II) NSCLC, with sensitivity and specificity of 70.4% and 99.0%, respectively. The serum levels of MIC-1 were associated with age (P = 0.001), gender (P = 0.030), and T stage (P = 0.022). Serum MIC-1 threshold of 1465 pg/ml was found in patients with poor early outcome, with sensitivity and specificity of 72.2% and 66.1%, respectively. The overall 3-year survival rate of NSCLC patients with high serum levels of MIC-1 (≥1465 pg/ml) was lower than that of NSCLC patients with low serum MIC-1 levels (77.6% vs. 94.8%). Multivariate Cox regression survival analysis showed that a high serum level of MIC-1 was an independent risk factor for reduced overall survival (hazard ratio = 3.37, 95% confidential interval: 1.09-10.42, P= 0.035).

CONCLUSION

The present study suggested that serum MIC-1 may be a potential diagnostic and prognostic biomarker for patients with early-stage NSCLC.

Screening for lung cancer: A systematic review and meta-analysis

OBJECTIVES

To examine evidence on benefits and harms of screening average to high-risk adults for lung cancer using chest radiology (CXR), sputum cytology (SC) and low-dose computed tomography (LDCT).

METHODS

This systematic review was conducted to provide up to date evidence for Canadian Task Force on Preventive Health Care (CTFPHC) lung cancer screening guidelines. Four databases were searched to March 31, 2015 along with utilizing a previous Cochrane review search. Randomized trials reporting benefits were included; any design was included for harms. Meta-analyses were performed if possible. PROSPERO #CRD42014009984.

RESULTS

Thirty-four studies were included. For lung cancer mortality there was no benefit of CXR screening, with or without SC. Pooled results from three small trials comparing LDCT to usual care found no significant benefits for lung cancer mortality. One large high quality trial showed statistically significant reductions of 20% in lung cancer mortality over a follow-up of 6.5years, for LDCT compared with CXR. LDCT screening was associated with: overdiagnosis of 10.99-25.83%; 11.18 deaths and 52.03 patients with major complications per 1000 undergoing invasive follow-up procedures; median estimate for false positives of 25.53% for baseline/once-only screening and 23.28% for multiple rounds; and 9.74 and 5.28 individuals per 1000 screened, with benign conditions underwent minor and major invasive follow-up procedures.

CONCLUSION

The evidence does not support CXR screening with or without sputum cytology for lung cancer. High quality evidence showed that in selected high-risk individuals, LDCT screening significantly reduced lung cancer mortality and all-cause mortality. However, for its implementation at a population level, the current evidence warrants the development of standardized practices for screening with LDCT and follow-up invasive testing to maximize accuracy and reduce potential associated harms.

Intentions to Undergo Lung Cancer Screening among Korean Men

Opportunistic screening for lung cancer is commonly conducted in Korea in accordance with physician recommendations and screenee's preferences. However, studies have yet to thoroughly examine the public's understanding of the risks posed by lung cancer screening. This study was conducted to assess changes in intentions to undergo lung cancer screening in response to being informed about exposure to radiation during low-dose computed tomography (LDCT) tests and to identify factors with the greatest influence thereon among Korean men. We conducted sub-group interviews among men chosen from the 2013 Korea National Cancer Screening Survey (KNCSS), a nationwide, population-based, cross-sectional survey of men aged 40 to 74 years and women aged 30 to 74 years. From 4100 participants in the KNCSS, 414 men who underwent any cancer screening test within the last 2 years were randomly selected for inclusion in this study. Via face-to-face interviews, their intentions to undergo lung cancer screening were assessed before and after being informed about exposure to radiation during LDCT testing. Of the 414 participants, 50% were current smokers. After receiving information on the benefits of the test, 95.1% stated an intention to undergo screening; this decreased to 81.6% after they received information on the harms of the test. The average decrease in intention rate was 35.3%. Smoking status, household income, and education level were not associated with lowered intentions to undergo lung cancer screening. Participants who were older than 60 years old (OR=0.56; 95% CI=0.33-0.96) and those with less concern for radiation exposure (OR=0.56; 95% CI=0.36-0.89) were less likely to lower their screening intentions. The results of this study suggest that there is a need to educate both non-smokers and former smokers on the harms of lung cancer screening.