Quantitative imaging workshop XIX: Utilizing quantitative thoracic imaging to optimize population health final summary

Lung cancer screening involves the use of thoracic CT for both detection and measurements of suspicious lung nodules to guide the screening management. Since lung cancer screening eligibility typically requires age over 50 years along with >20 pack-year tobacco exposure, thoracic CT scans also frequently reveal evidence for pulmonary emphysema as well as coronary artery calcification. These three thoracic diseases are collectively three of the leading causes of premature death across the world. Screening for the major thoracic diseases in this heavily tobacco-exposed cohort is broadening the focus of lung cancer screening to a more comprehensive health evaluation including discussing the relevance of screen-detected findings of the heart and lung parenchyma. The status and implications of these emerging issues were reviewed in a multidisciplinary workshop focused on the process of quantitative imaging in the lung cancer screening setting to guide the evolution of this important new area of public health.

The International Association for the Study of Lung Cancer Early Lung Imaging Confederation Open-Source Deep Learning and Quantitative Measurement Initiative

INTRODUCTION

With global adoption of computed tomography (CT) lung cancer screening, there is increasing interest to use artificial intelligence (AI) deep learning methods to improve the clinical management process. To enable AI research using an open-source, cloud-based, globally distributed, screening CT imaging data set and computational environment that are compliant with the most stringent international privacy regulations that also protect the intellectual properties of researchers, the International Association for the Study of Lung Cancer sponsored development of the Early Lung Imaging Confederation (ELIC) resource in 2018. The objective of this report is to describe the updated capabilities of ELIC and illustrate how this resource can be used for clinically relevant AI research.

METHODS

In this second phase of the initiative, metadata and screening CT scans from two time points were collected from 100 screening participants in seven countries. An automated deep learning AI lung segmentation algorithm, automated quantitative emphysema metrics, and a quantitative lung nodule volume measurement algorithm were run on these scans.

RESULTS

A total of 1394 CTs were collected from 697 participants. The LAV950 quantitative emphysema metric was found to be potentially useful in distinguishing lung cancer from benign cases using a combined slice thickness more than or equal to 2.5 mm. Lung nodule volume change measurements had better sensitivity and specificity for classifying malignant from benign lung nodules when applied to solid lung nodules from high-quality CT scans.

CONCLUSIONS

These initial experiments revealed that ELIC can support deep learning AI and quantitative imaging analyses on diverse and globally distributed cloud-based data sets.

The International Association for the Study of Lung Cancer Early Lung Imaging Confederation

PURPOSE

To improve outcomes for lung cancer through low-dose computed tomography (LDCT) early lung cancer detection. The International Association for the Study of Lung Cancer is developing the Early Lung Imaging Confederation (ELIC) to serve as an open-source, international, universally accessible environment to analyze large collections of quality-controlled LDCT images and associated biomedical data for research and routine screening care.

METHODS

ELIC is an international confederation that allows access to efficiently analyze large numbers of high-quality computed tomography (CT) images with associated de-identified clinical information without moving primary imaging/clinical or imaging data from its local or regional site of origin. Rather, ELIC uses a cloud-based infrastructure to distribute analysis tools to the local site of the stored imaging and clinical data, thereby allowing for research and quality studies to proceed in a vendor-neutral, collaborative environment. ELIC’s hub-and-spoke architecture will be deployed to permit analysis of CT images and associated data in a secure environment, without any requirement to reveal the data itself (ie, privacy protecting). Identifiable data remain under local control, so the resulting environment complies with national regulations and mitigates against privacy or data disclosure risk.

RESULTS

The goal of pilot experiments is to connect image collections of LDCT scans that can be accurately analyzed in a fashion to support a global network using methodologies that can be readily scaled to accrued databases of sufficient size to develop and validate robust quantitative imaging tools.

CONCLUSION

This initiative can rapidly accelerate improvements to the multidisciplinary management of early, curable lung cancer and other major thoracic diseases (eg, coronary artery disease and chronic obstructive pulmonary disease) visualized on a screening LDCT scan. The addition of a facile, quantitative CT scanner image quality conformance process is a unique step toward improving the reliability of clinical decision support with CT screening worldwide.

From clinical specimens to human cancer preclinical models-a journey the NCI-cell line database-25 years later

The intramural the National Cancer Institute (NCI) and more recently the University of Texas Southwestern Medical Center with many different collaborators comprised a complex, multi-disciplinary team that collaborated to generated large, comprehensively annotated, cell-line related research resources which includes associated clinical, and molecular characterization data. This material has been shared in an anonymized fashion to accelerate progress in overcoming lung cancer, the leading cause of cancer death across the world. However, this cell line collection also includes a range of other cancers derived from patient-donated specimens that have been remarkably valuable for other types of cancer and disease research. A comprehensive analysis conducted by the NCI Center for Research Strategy of the 278 cell lines reported in the original Journal of Cellular Biochemistry Supplement, documents that these cell lines and related products have since been used in more than 14 000 grants, and 33 207 published scientific reports. This has resulted in over 1.2 million citations using at least one cell line. Many publications involve the use of more than one cell line, to understand the value of the resource collectively rather than individually; this method has resulted in 2.9 million citations. In addition, these cell lines have been linked to 422 clinical trials and cited by 4700 patents through publications. For lung cancer alone, the cell lines have been used in the research cited in the development of over 70 National Comprehensive Cancer Network clinical guidelines. Finally, it must be underscored again, that patient altruism enabled the availability of this invaluable research resource.

Quality assurance and quantitative imaging biomarkers in low-dose CT lung cancer screening

After years of assessment through controlled clinical trials, low-dose CT screening for lung cancer is becoming part of clinical practice. As with any cancer screening test, those undergoing lung cancer screening are not being evaluated for concerning signs or symptoms, but are generally in good health and proactively trying to prevent premature death. Given the resultant obligation to achieve the screening aim of early diagnosis while also minimizing the potential for morbidity from workup of indeterminate but ultimately benign screening abnormalities, careful implementation of screening with conformance to currently recognized best practices and a focus on quality assurance is essential. In this review, we address the importance of each component of the screening process to optimize the effectiveness of CT screening, discussing options for quality assurance at each step. We also discuss the potential added advantages, quality assurance requirements and current status of quantitative imaging biomarkers related to lung cancer screening. Finally, we highlight suggestions for improvements and needs for further evidence in evaluating the performance of CT screening as it transitions from the research trial setting into daily clinical practice.

Moonshot Acceleration Factor: Medical Imaging

Medical imaging is essential to screening, early diagnosis, and monitoring responses to cancer treatments and, when used with other diagnostics, provides guidance for clinicians in choosing the most effective patient management plan that maximizes survivorship and quality of life. At a gathering of agency officials, patient advocacy organizations, industry/professional stakeholder groups, and clinical/basic science academicians, recommendations were made on why and how one should build a "cancer knowledge network" that includes imaging. Steps to accelerate the translation and clinical adoption of cancer discoveries to meet the goals of the Cancer Moonshot include harnessing computational power and architectures, developing data sharing policies, and standardizing medical imaging and in vitro diagnostics. Cancer Res; 77(21); 5717-20. ©2017 AACR.

Scientific Advances in Thoracic Oncology 2016

Lung cancer care is rapidly changing with advances in genomic testing, the development of next-generation targeted kinase inhibitors, and the continued broad study of immunotherapy in new settings and potential combinations. The International Association for the Study of Lung Cancer and the Journal of Thoracic Oncology publish this annual update to help readers keep pace with these important developments. Experts in thoracic cancer and care provide focused updates across multiple areas, including prevention and early detection, molecular diagnostics, pathology and staging, surgery, adjuvant therapy, radiotherapy, molecular targeted therapy, and immunotherapy for NSCLC, SCLC, and mesothelioma. Quality and value of care and perspectives on the future of lung cancer research and treatment have also been included in this concise review.

Lung cancer: current therapies and new targeted treatments

Lung cancer is the most frequent cause of cancer-related deaths worldwide. Every year, 1·8 million people are diagnosed with lung cancer, and 1·6 million people die as a result of the disease. 5-year survival rates vary from 4-17% depending on stage and regional differences. In this Seminar, we discuss existing treatment for patients with lung cancer and the promise of precision medicine, with special emphasis on new targeted therapies. Some subgroups, eg-patients with poor performance status and elderly patients-are not specifically addressed, because these groups require special treatment considerations and no frameworks have been established in terms of new targeted therapies. We discuss prevention and early detection of lung cancer with an emphasis on lung cancer screening. Although we acknowledge the importance of smoking prevention and cessation, this is a large topic beyond the scope of this Seminar.

Volumes Learned: It Takes More Than Size to "Size Up" Pulmonary Lesions

RATIONALE AND OBJECTIVES

This study aimed to review the current understanding and capabilities regarding use of imaging for noninvasive lesion characterization and its relationship to lung cancer screening and treatment.

MATERIALS AND METHODS

Our review of the state of the art was broken down into questions about the different lung cancer image phenotypes being characterized, the role of imaging and requirements for increasing its value with respect to increasing diagnostic confidence and quantitative assessment, and a review of the current capabilities with respect to those needs.

RESULTS

The preponderance of the literature has so far been focused on the measurement of lesion size, with increasing contributions being made to determine the formal performance of scanners, measurement tools, and human operators in terms of bias and variability. Concurrently, an increasing number of investigators are reporting utility and predictive value of measures other than size, and sensitivity and specificity is being reported. Relatively little has been documented on quantitative measurement of non-size features with corresponding estimation of measurement performance and reproducibility.

CONCLUSIONS

The weight of the evidence suggests characterization of pulmonary lesions built on quantitative measures adds value to the screening for, and treatment of, lung cancer. Advanced image analysis techniques may identify patterns or biomarkers not readily assessed by eye and may also facilitate management of multidimensional imaging data in such a way as to efficiently integrate it into the clinical workflow.

Role of the Quantitative Imaging Biomarker Alliance in optimizing CT for the evaluation of lung cancer screen-detected nodules

The Quantitative Imaging Biomarker Alliance (QIBA) is a multidisciplinary consortium sponsored by the RSNA to define processes that enable the implementation and advancement of quantitative imaging methods described in a QIBA profile document that outlines the process to reliably and accurately measure imaging features. A QIBA profile includes factors such as technical (product-specific) standards, user activities, and relationship to a clinically meaningful metric, such as with nodule measurement in the course of CT screening for lung cancer. In this report, the authors describe how the QIBA approach is being applied to the measurement of small pulmonary nodules such as those found during low-dose CT-based lung cancer screening. All sources of variance with imaging measurement were defined for this process. Through a process of experimentation, literature review, and assembly of expert opinion, the strongest evidence was used to define how to best implement each step in the imaging acquisition and evaluation process. This systematic approach to implementing a quantitative imaging biomarker with standardized specifications for image acquisition and postprocessing for a specific quantitative measurement of a pulmonary nodule results in consistent performance characteristics of the measurement (eg, bias and variance). Implementation of the QIBA small nodule profile may allow more efficient and effective clinical management of the diagnostic workup of individuals found to have suspicious pulmonary nodules in the course of lung cancer screening evaluation.

Lung Cancer Workshop XI: Tobacco-Induced Disease: Advances in Policy, Early Detection and Management

The Prevent Cancer Foundation Lung Cancer Workshop XI: Tobacco-Induced Disease: Advances in Policy, Early Detection and Management was held in New York, NY on May 16 and 17, 2014. The two goals of the Workshop were to define strategies to drive innovation in precompetitive quantitative research on the use of imaging to assess new therapies for management of early lung cancer and to discuss a process to implement a national program to provide high quality computed tomography imaging for lung cancer and other tobacco-induced disease. With the central importance of computed tomography imaging for both early detection and volumetric lung cancer assessment, strategic issues around the development of imaging and ensuring its quality are critical to ensure continued progress against this most lethal cancer.

Evaluation of an interactive science publishing tool: toward enabling three-dimensional analysis of medical images

RATIONALE AND OBJECTIVES

Higher resolution medical imaging platforms are rapidly emerging, but there is a challenge in applying these tools in a clinically meaningful way. The purpose of the current study was to evaluate a novel three-dimensional (3D) software imaging environment, known as interactive science publishing (ISP), in appraising 3D computed tomography images and to compare this approach with traditional planar (2D) imaging in a series of lung cancer cases.

MATERIALS AND METHODS

Twenty-four physician volunteers at different levels of training across multiple specialties were recruited to evaluate eight lung cancer-related clinical vignettes. The volunteers were asked to compare the performance of traditional 2D versus the ISP 3D imaging in assessing different visualization environments for diagnostic and measurement processes and to further evaluate the ISP tool in terms of general satisfaction, usability, and probable applicability.

RESULTS

Volunteers were satisfied with both imaging methods; however, the 3D environment had significantly higher ratings. Measurement performance was comparable using both traditional 2D and 3D image evaluation. Physicians not trained in 2D measurement approaches versus those with such training demonstrated better performance with ISP and preferred working in the ISP environment.

CONCLUSIONS

Recent postgraduates with only modest self-administered training performed equally well on 3D and 2D cases. This suggests that the 3D environment has no reduction in accuracy over the conventional 2D approach, while providing the advantage of a digital environment for cross-disciplinary interaction for shared problem solving. Exploration of more effective, efficient, self-directed training could potentially result in further improvement in image evaluation proficiency and potentially decrease training costs.

Issues with implementing a high-quality lung cancer screening program

After a comprehensive review of the evidence, the United States Preventive Services Task Force recently endorsed screening with low-dose computed tomography as an early detection approach that has the potential to significantly reduce deaths due to lung cancer. Prudent implementation of lung cancer screening as a high-quality preventive health service is a complex challenge. The clinical evaluation and management of high-risk cohorts in the absence of symptoms mandates an approach that differs significantly from that of symptom-detected lung cancer. As with other cancer screenings, it is essential to provide to informed at-risk individuals a safe, high-quality, cost-effective, and accessible service. In this review, the components of a successful screening program are discussed as we begin to disseminate lung cancer screening as a national resource to improve outcomes with this lethal cancer. This information about lung cancer screening will assist clinicians with communications about the potential benefits and harms of this service for high-risk individuals considering participation in the screening process.

Lung cancer screening guidelines: common ground and differences

Lung cancer accounts for almost one-third of all cancer related deaths. Lung cancer risk persists even after smoking cessation and so many lung cancers now are diagnosed in former smokers. Five-year survival of lung cancer has marginally improved over decades and significantly lags behind that of colon, breast and prostate cancer. Over the past one decade, lung cancer screening trials have shown promising results. Results from National Lung Cancer Screening Trial (NLST), have shown a significant 20% reduction in mortality with annual low dose computed tomography (LDCT) screening. Based on these results, annual LDCT testing has been recommended for lung cancer screening in high risk population. However, development and acceptance of lung cancer screening as a public health policy is still in the nascent stages. Major concerns relate to risk of radiation, overdiagnosis bias, proportion of false positives and cost benefit analysis. This article reviews the literature pertaining to lung cancer screening guidelines and above mentioned concerns.

Addressing tobacco use in patients with cancer: a survey of American Society of Clinical Oncology members

PURPOSE

Assessing tobacco use and providing cessation support is recommended by the American Society for Clinical Oncology (ASCO). The purpose of this study was to evaluate practice patterns and perceptions of tobacco use and barriers to providing cessation support for patients with cancer.

METHODS

In 2012, an online survey was sent to 18,502 full ASCO members asking about their practice patterns regarding tobacco assessment, cessation support, perceptions of tobacco use, and barriers to providing cessation support for patients with cancer. Responses from 1,197 ASCO members are reported.

RESULTS

At initial visit, most respondents routinely ask patients about tobacco use (90%), ask patients to quit (80%), and advise patients to stop using tobacco (84%). However, only 44% routinely discuss medication options with patients, and only 39% provide cessation support. Tobacco assessments decrease at follow-up assessments. Most respondents (87%) agree or strongly agree that smoking affects cancer outcomes, and 86% believe cessation should be a standard part of clinical cancer care. However, only 29% report adequate training in tobacco cessation interventions. Inability to get patients to quit (72%) and patient resistance to treatment (74%) are dominant barriers to cessation intervention, but only 8% describe cessation as a waste of time.

CONCLUSION

Among ASCO members who responded to an online survey about their practice patterns regarding tobacco, most believe that tobacco cessation is important and frequently assess tobacco at initial visit, but few provide cessation support. Interventions are needed to increase access to tobacco cessation support for patients with cancer.

Addressing tobacco use and cessation in cancer patients: Practices, perceptions, and barriers reported by oncology providers

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Background: Tobacco use is associated with adverse outcomes in cancer patients, but there are limited data on tobacco cessation support by oncology providers. Methods: Duplicate surveys were sent to the membership of the International Association for the Study of Lung Cancer (IASLC) and the American Society of Clinical Oncology (ASCO) asking about tobacco assessment and cessation practices, perceptions of tobacco use by cancer patients, and barriers to implementing tobacco cessation. The results of 1,507 responses from IASLC and 1,197 responses from ASCO are reported. Results: At initial consult, most respondents asked about tobacco use (90% in both surveys), asked if smokers would quit tobacco use (79-80%), advised patients to stop smoking (81-82%). Most respondents felt that tobacco affects cancer outcomes (87-92%) and that tobacco cessation should be a standard part of clinical care (86-90%). However, few discussed medication options (40-44%) or actively provided smoking cessation assistance (39% in both surveys). Fewer respondents asked about tobacco use at follow-up and few reported adequate tobacco cessation training (29-33%). Dominant barriers to providing cessation interventions included patient resistance to cessation treatment (67-74%) and inability to get patients to quit tobacco use (58-72%), but very few believed tobacco cessation was a waste of time (8-12%). Lack of time, reimbursement, lack of training, and lack of resources were reported as barriers in less than 50% of respondents. Conclusions: Oncology providers feel tobacco affects cancer outcomes and cessation should be a standard part of clinical care. Most assess tobacco use, but few discuss medication options or provide active cessation support. Efforts are needed to improve cessation methods in cancer patients and to improve access to tobacco cessation support for cancer patients.

Two lipids based on lipidomics as novel biomarkers for early detection of squamous cell lung cancer

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Background: Lipids play roles in membrane structure, energy storage, and signal transduction as well as lung cancer. Lipidomics, a new technology aims to measure all the lipids in a cell, has not been applied to diagnostic test development for a variety of cancer types. Here, we adopt lipidomics as a means to identify plasma lipid markers for the early detection of lung cancer and complement CT-based methods for lung cancer screening. Methods: Using mass spectrometry, we profiled 390 individual lipids in a training discovery cohort comprised of cohorts that were either at “high-risk” for lung cancer (n=22) and squamous cell carcinoma at early stages (n=22). Cases had a minimum of two years clinical follow-up and were matched in terms of race, sex, age and smoking status. Gain ratio feature selection and local weighted classification model were employed to find the best training classifier, which was further validated against an additional cohort, including high-risk individuals (n= 20) and squamous cell carcinoma patients (n=17). Results: In the training discovery stage, we found 20 distinct lipids that were significantly distributed between high-risk and cases of squamous cell carcinoma. We further defined a two lipid marker panel had a training accuracy at 95.5% sensitivity, 90.9% specificity and 95.2% AUC (Area under ROC curve). The validation accuracy against the additional cohort is 100.0% sensitivity, 90.0% specificity and 99.0% AUC (Table). The power for sample size we used in both discovery training and validation stages were over 90%. Conclusions: Using lipidomics we identified two lipid markers capable of discerning cases of squamous cell carcinoma from individuals at high risk for lung cancer, with a high sensitivity, specificity and accuracy. The markers maybe further developed as a quick, safe blood test for early diagnosis of squamous cell lung cancer and reduce unnecessary follow-up imaging or invasive procedures. [Table: see text]

Not significant but important

Armstrong and colleagues report the result of a large Phase IIb randomized trial evaluating the effectiveness of a preparation of the Bowman Birk Inhibitor compared with an oral placebo in reversing the extent of oral leukoplakia as measured visually by pathology or a battery of intermediate end points. In this editorial, we review the report of this negative clinical trials result to highlight the clinical trial process used in evaluating this previously promising chemoprevention agent. Publishing this report is important to address concerns with publication bias. The challenges in running a chemoprevention trial are reviewed with suggestions to enhance progress going forward. Conceptually, developing drugs to intercept the early stages of carcinogenesis is very attractive, but progress in this area has been slow. Two opportunities to overcome this reality are discussed. These measures include the broader use of neoadjuvant, window-of-opportunity trials with new candidate chemoprevention agents to get more textured information about the mechanistic impact of the drug exposure in previously untreated early tumor tissue. In addition, we discuss the use of new intermediate end point markers such as with optical imaging tools to obtain a more objective and quantitative assessment of drug response.

An actuarial analysis shows that offering lung cancer screening as an insurance benefit would save lives at relatively low cost

Lung cancer screening is not established as a public health practice, yet the results of a recent large randomized controlled trial showed that screening with low-dose spiral computed tomography reduces lung cancer mortality. Using actuarial models, this study estimated the costs and benefits of annual lung cancer screening offered as a commercial insurance benefit in the high-risk US population ages 50-64. Assuming current commercial reimbursement rates for treatment, we found that screening would cost about $1 per insured member per month in 2012 dollars. The cost per life-year saved would be below $19,000, an amount that compares favorably with screening for cervical, breast, and colorectal cancers. Our results suggest that commercial insurers should consider lung cancer screening of high-risk individuals to be high-value coverage and provide it as a benefit to people who are at least fifty years old and have a smoking history of thirty pack-years or more. We also believe that payers and patients should demand screening from high-quality, low-cost providers, thus helping set an example of efficient system innovation.

The American Association for Thoracic Surgery guidelines for lung cancer screening using low-dose computed tomography scans for lung cancer survivors and other high-risk groups

OBJECTIVE

Lung cancer is the leading cause of cancer death in North America. Low-dose computed tomography screening can reduce lung cancer-specific mortality by 20%.

METHOD

The American Association for Thoracic Surgery created a multispecialty task force to create screening guidelines for groups at high risk of developing lung cancer and survivors of previous lung cancer.

RESULTS

The American Association for Thoracic Surgery guidelines call for annual lung cancer screening with low-dose computed tomography screening for North Americans from age 55 to 79 years with a 30 pack-year history of smoking. Long-term lung cancer survivors should have annual low-dose computed tomography to detect second primary lung cancer until the age of 79 years. Annual low-dose computed tomography lung cancer screening should be offered starting at age 50 years with a 20 pack-year history if there is an additional cumulative risk of developing lung cancer of 5% or greater over the following 5 years. Lung cancer screening requires participation by a subspecialty-qualified team. The American Association for Thoracic Surgery will continue engagement with other specialty societies to refine future screening guidelines.

CONCLUSIONS

The American Association for Thoracic Surgery provides specific guidelines for lung cancer screening in North America.

Development of The American Association for Thoracic Surgery guidelines for low-dose computed tomography scans to screen for lung cancer in North America: recommendations of The American Association for Thoracic Surgery Task Force for Lung Cancer Screening and Surveillance

OBJECTIVE

The study objective was to establish The American Association for Thoracic Surgery (AATS) lung cancer screening guidelines for clinical practice.

METHODS

The AATS established the Lung Cancer Screening and Surveillance Task Force with multidisciplinary representation including 4 thoracic surgeons, 4 thoracic radiologists, 4 medical oncologists, 1 pulmonologist, 1 pathologist, and 1 epidemiologist. Members have engaged in interdisciplinary collaborations regarding lung cancer screening and clinical care of patients with, and at risk for, lung cancer. The task force reviewed the literature, including screening trials in the United States and Europe, and discussed local best clinical practices in the United States and Canada on 4 conference calls. A reference library supported the discussions and increased individual study across disciplines. The task force met to review the literature, state of clinical practice, and recommend consensus-based guidelines.

RESULTS

Nine of 14 task force members were present at the meeting, and 3 participated by telephone. Two absent task force members were polled afterward. Six unanimous recommendations and supporting work-up algorithms were presented to the Council of the AATS at the 2012 annual meeting in San Francisco, California.

CONCLUSIONS

Annual lung cancer screening and surveillance with low-dose computed tomography is recommended for smokers and former smokers with a 30 pack-year history of smoking and long-term lung cancer survivors aged 55 to 79 years. Screening may begin at age 50 years with a 20 pack-year history of smoking and additional comorbidity that produces a cumulative risk of developing lung cancer of 5% or greater over the following 5 years. Screening should be undertaken with a subspecialty qualified interdisciplinary team. Patient risk calculator application and intersociety engagement will provide data needed to refine future lung cancer screening guidelines.

Abstract IA19: New opportunities to the personalization and management of early lung cancer

Lung cancer is the most lethal cancer across the globe with 5-year mortality rates from 80 to over 90% related to the frequency of metastatic disease at initial diagnosis. While metastatic disease is generally incurable, early lung cancer when found still localized to the airways, can frequently be cured. A recent NCI-sponsored, randomized trial of helical CT compared to chest X-ray screening in a high risk cohort reported that the CT arm resulted in a 20% reduction in lung cancer mortality. Coupled with the recent comprehensive revision of lung cancer staging classification, there is a much clearer understanding of the relationship between primary tumor size and lung cancer outcome. The finding that smaller lung cancers are more frequently curable provides a firm conceptual framework for population-based early lung cancer detection strategies as a productive approach to significantly improve lung cancer outcomes.

As was demonstrated by reports from both I-ELCAP and the NELSON clinical trials groups, detection rates of stage I lung cancer with helical CT could exceed 70%. Further, the expense and morbidity of invasive diagnostic work-up strategy could be efficient focused based on the suggestion by Yankelevitz and co-workers to use measurement of nodule growth rate on serial CT scans as a biomarker to identify clinically aggressive lung cancers. In this fashion as reported by van Klaveren and co-workers, volumetric determination of suspected lung cancers could enable efficient and accurate lung cancer case detection.

The surgical management of early stage lung cancers is increasingly employing video-assisted thoroscopic surgery. Recent studies demonstrate lower complications and more favorable operative mortality rates compared to standard, open thorocotomy approaches. The net effect of these developments is to reduce the possibility of over-treatment in the lung cancer screening setting. These surgical procedures do provide sufficient primary tumor tissue which allows comprehensive molecular analysis of the tumor to identify critical signaling pathways.

As the evolution of effective and efficient early lung cancer management unfolds, opportunities exist to better define the relevant at-risk population for screening approaches with the ability to calibrate the frequency of screening relative to the measured risk profile. Information from the imaging and tumor tissue evaluation of detected cases may also provide insight as to the molecular underpinnings of the cancer. This characterization of the primary tumor may subsequently guide the development of more tailored adjuvant therapies and eventually chemopreventive strategies that would be targeted to the specific pathogenic mechanisms of lung carcinogenesis.

The continuous improvement of early lung cancer management is an appropriate area to apply the process improvement strategies proposed by the Institute of Medicine in their Learning Health System approach. In this way, the component elements of the screening process can be optimized and personalized to allow overall progress in advancing public health benefit with CT-based lung cancer screening.

hnRNP A2/B1 modulates epithelial-mesenchymal transition in lung cancer cell lines

Heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1) has been reported to be overexpressed in lung cancer and in other cancers such as breast, pancreas, and liver. However, a mechanism linking hnRNP A2/B1 overexpression and progression to cancer has not yet been definitively established. To elucidate this mechanism, we have silenced hnRNPA2/B1 mRNA in non-small-cell lung cancer cell lines A549, H1703, and H358. These cell lines present different levels of expression of epithelial-to-mesenchymal transition (EMT) markers such as E-cadherin, fibronectin, and vimentin. Microarray expression analysis was performed to evaluate the effect of silencing hnRNP A2/B1 in A549 cells. We identified a list of target genes, affected by silencing of hnRNP A2/B1, that are involved in regulation of migration, proliferation, survival, and apoptosis. Silencing hnRNP A2/B1 induced formation of cell clusters and increased proliferation. In the anchorage-independent assay, silencing hnRNP A2/B1 increased colony formation by 794% in A549 and 174% in H1703 compared with a 25% increase in proliferation, in both cell lines, in a two-dimensional proliferation assay. Silencing hnRNP A2/B1 decreased migration in intermediate cell line A549 and mesenchymal cell line H1703; however, no changes in proliferation were observed in epithelial cell line H358. Silencing hnRNP A2/B1 in A549 and H1703 cells correlated with an increase of E-cadherin expression and downregulation of the E-cadherin inhibitors Twist1 and Snai1. These data suggest that expression of hnRNP A2/B1 may play a role in EMT, in nonepithelial lung cancer cell lines A549 and H1703, through the regulation of E-cadherin expression.

A quantitative method for estimating individual lung cancer risk

RATIONALE AND OBJECTIVES

Lung cancer is caused primarily by repeated exposure to carcinogenic particulate matter and noxious gasses with high particulate deposition localized to airway bifurcations and the lung periphery. The quantitative measurement and analysis of these sites has the potential to stratify lung cancer risk. The aim of this preliminary study was to assess the performance of a new method for estimating individual lung cancer risk based on the analysis of airway bifurcations on high-resolution (HR) computed tomographic (CT) scanning and spirometry.

MATERIALS AND METHODS

One hundred eight subjects with spirometry and thin-slice CT data were selected from a CT screening study including 15 patients with early lung cancer and 93 age-matched and pack-year-matched controls. A subset of seven patients with cancer and 72 controls were scanned with 1-mm CT slice thickness, representing an HR case subset. A quantitative lung cancer risk index method was developed on the basis of airway bifurcation x-ray attenuation combined with the ratio of forced expiratory volume in 1 second to forced vital capacity. Cochran-Mantel-Haenszel and conditional logistic regression tests were used to analyze performance.

RESULTS

Cochran-Mantel-Haenszel crude analysis revealed a cancer detection sensitivity and specificity of 67% and 72% for all cases and 100% and 73% for the HR case subset, respectively. Conditional logistic regression showed that a 0.0328 increase in lung cancer risk index was associated with odds ratios of 1.84 (95% confidence interval, 1.18-2.85) for the full data set (P = .0067) and 2.89 (95% confidence interval, 1.02-8.19) for the HR subset (P = .0467).

CONCLUSIONS

A preliminary evaluation of a new lung cancer risk estimation method based on thin slice CT and spirometry showed a statistically significant association with lung cancer.

The Liverpool Statement 2005: priorities for the European Union/United States spiral computed tomography collaborative group

The Liverpool Statement 2005 was developed at the Fourth International Lung Cancer Molecular Biomarkers Workshop in Liverpool (October 27-29, 2005) and focused on the priorities for the European Union/United States (EU-US) Spiral Computed Tomography (CT) Collaborative Group. The application of spiral CT technology for early lung cancer screening has gained enormous momentum in the past 5 years. The EU-US Spiral CT Collaboration was initiated in 2001 in Liverpool, and subsequent meetings throughout Europe have resulted in the development of collaborative protocols and minimal data sets that provide a mechanism for the different trial groups to work together, with the ultimate aim to pool results. Considerable progress has been made with major national screening trials in the U.S. and Europe, which include IELCAP, NLST, and NELSON. The major objective of this international collaboration is the planned cross-analysis of the individual studies after they are reported. The EU-US researchers have agreed to a number of long-term objectives and to explore strategic areas for harmonization of complementary investigations.