Faculty Bibliography

BACKGROUND:Molecular biomarkers have the potential to improve the current state of early lung cancer detection. The goal of this project was to develop a policy statement that provides guidance about the level of evidence required to determine that a molecular biomarker, used to support early lung cancer detection, is appropriate for clinical use. METHODS:An ad hoc project steering committee was formed, to include individuals with expertise in the early detection of lung cancer and molecular biomarker development, from inside and outside of the Assembly on Thoracic Oncology. Key questions, generated from the results of a survey of the project steering committee, were discussed at an in-person meeting. Results of the discussion were summarized in a policy statement that was circulated to the steering committee and revised multiple times to achieve consensus. RESULTS:With a focus on the clinical applications of lung cancer screening and lung nodule evaluation, the policy statement outlines categories of results that should be reported in the early phases of molecular biomarker development, discusses the level of evidence that would support study of the clinical utility, describes the outcomes that should be proven to consider a molecular biomarker clinically useful, and suggests study designs capable of assessing these outcomes. CONCLUSIONS:The application of molecular biomarkers to assist with the early detection of lung cancer has the potential to substantially improve our ability to select patients for lung cancer screening, and to assist with the characterization of indeterminate lung nodules. We have described relevant considerations and have suggested standards to apply when determining whether a molecular biomarker for the early detection of lung cancer is ready for clinical use.

RATIONALE:Smoking cessation counseling in conjunction with low-dose computed tomography (LDCT) lung cancer screening is recommended in multiple clinical practice guidelines. The best approach for integrating effective smoking cessation interventions within this setting is unknown. OBJECTIVES:To summarize evidence, identify research gaps, prioritize topics for future research, and propose standardized tools for use in conducting research on smoking cessation interventions within the LDCT lung cancer screening setting. METHODS:The American Thoracic Society convened a multistakeholder committee with expertise in tobacco dependence treatment and/or LDCT screening. During an in-person meeting, evidence was reviewed, research gaps were identified, and key questions were generated for each of three research domains: (1) target population to study; (2) adaptation, development, and testing of interventions; and (3) implementation of interventions with demonstrated efficacy. We also identified standardized measures for use in conducting this research. A larger stakeholder panel then ranked research questions by perceived importance in an online survey. Final prioritization was generated hierarchically on the basis of average rank assigned. RESULTS:There was little consensus on which questions within the population domain were of highest priority. Within the intervention domain, research to evaluate the effectiveness in the lung cancer screening setting of evidence-based smoking cessation interventions shown to be effective in other contexts was ranked highest. In the implementation domain, stakeholders prioritized understanding strategies to identify and overcome barriers to integrating smoking cessation in lung cancer screening settings. CONCLUSIONS:This statement offers an agenda to stimulate research surrounding the integration and implementation of smoking cessation interventions with LDCT lung cancer screening.

Gene-by-environment (G × E) interactions are important in explaining the missing heritability and understanding the causation of complex diseases, but a single, moderately sized study often has limited statistical power to detect such interactions. With the increasing need for integrating data and reporting results from multiple collaborative studies or sites, debate over choice between mega- versus meta-analysis continues. In principle, data from different sites can be integrated at the individual level into a "mega" data set, which can be fit by a joint "mega-analysis." Alternatively, analyses can be done at each site, and results across sites can be combined through a "meta-analysis" procedure without integrating individual level data across sites. Although mega-analysis has been advocated in several recent initiatives, meta-analysis has the advantages of simplicity and feasibility, and has recently led to several important findings in identifying main genetic effects. In this paper, we conducted empirical and simulation studies, using data from a G × E study of lung cancer, to compare the mega- and meta-analyses in four commonly used G × E analyses under the scenario that the number of studies is small and sample sizes of individual studies are relatively large. We compared the two data integration approaches in the context of fixed effect models and random effects models separately. Our investigations provide valuable insights in understanding the differences between mega- and meta-analyses in practice of combining small number of studies in identifying G × E interactions.

BACKGROUND:Bronchoscopy is often the initial diagnostic procedure performed in patients with pulmonary lesions suggestive of lung cancer. A bronchial genomic classifier was previously validated to identify patients at low risk for lung cancer after an inconclusive bronchoscopy. In this study, we evaluated the potential of the classifier to reduce invasive procedure utilization in patients with suspected lung cancer. METHODS:In two multicenter trials of patients undergoing bronchoscopy for suspected lung cancer, the classifier was measured in normal-appearing bronchial epithelial cells from a mainstem bronchus. Among patients with low and intermediate pretest probability of cancer (n = 222), subsequent invasive procedures after an inconclusive bronchoscopy were identified. Estimates of the ability of the classifier to reduce unnecessary procedures were calculated. RESULTS:Of the 222 patients, 188 (85%) had an inconclusive bronchoscopy and follow-up procedure data available for analysis. Seventy-seven (41%) patients underwent an additional 99 invasive procedures, which included surgical lung biopsy in 40 (52%) patients. Benign and malignant diseases were ultimately diagnosed in 62 (81%) and 15 (19%) patients, respectively. Among those undergoing surgical biopsy, 20 (50%) were performed in patients with benign disease. If the classifier had been used to guide decision making, procedures could have been avoided in 50% (21 of 42) of patients undergoing further invasive testing. Further, among 35 patients with an inconclusive index bronchoscopy who were diagnosed with lung cancer, the sensitivity of the classifier was 89%, with 4 (11%) patients having a false-negative classifier result. CONCLUSIONS:Invasive procedures after an inconclusive bronchoscopy occur frequently, and most are performed in patients ultimately diagnosed with benign disease. Using the genomic classifier as an adjunct to bronchoscopy may reduce the frequency and associated morbidity of these invasive procedures. TRIAL REGISTRY/BACKGROUND:ClinicalTrials.gov; Nos. NCT01309087 and NCT00746759; URL: www.clinicaltrials.gov.

RATIONALE:Radiographic lung cancer screening guidelines and coverage requirements warrant a shared decision-making process. Guidance is needed regarding how to conduct shared decision making effectively. A useful organizing theme should include consideration of a patient's response to and tolerance of uncertainty associated with lung cancer screening. OBJECTIVES:The objectives of this study are to: (1) describe how patients respond to specific categories of uncertainty in the context of lung cancer screening, and (2) inform strategies for addressing concerns about uncertainty as part of the shared decision making. METHODS:We performed two series of structured interviews on participants in a convenience sample of current or former cigarette smokers recruited from primary care and pulmonary practices in Philadelphia. An interview guide included prompts related to benefits, harms, and responses to general and specific types of uncertainty (stochastic, statistical, and evidentiary) associated with lung cancer screening. Interviews were audio-recorded, transcribed, and independently coded by two investigators. An inductive analysis was conducted, and major themes were identified. MEASUREMENTS AND MAIN RESULTS:Twenty-two adults participated in the study. Sixty-eight percent were men, 72% were black or African American, and 50% met U.S. Preventive Services Task Force criteria for lung cancer screening. The primary themes to emerge from our study were: (1) the desire to decrease uncertainty may motivate lung cancer screening decisions; (2) uncertainty is an attribute of health states that impacts how patients weigh benefits and harms of lung cancer screening; (3) patient understanding and tolerance of uncertainty varies across stochastic, statistical, and evidentiary uncertainty; and (4) provider-patient communication may mitigate intolerance of uncertainty in the context of lung cancer screening. CONCLUSIONS:A systematic approach to understanding and addressing patients' concerns about uncertainty in the context of lung cancer screening can guide a patient-centered approach to shared decision making. The results of this study can inform provider-patient communication strategies regarding the decision to perform radiographic lung cancer screening.

PURPOSE/OBJECTIVE:Surveillance PET after curative-intent treatment of non-small-cell lung cancer (NSCLC) or colorectal cancer (CRC) is not clearly supported by available evidence or the Choosing Wisely campaign. However, the frequency of PET imaging during the surveillance period is relatively unknown. METHODS:Using Surveillance, Epidemiology, and End Results-Medicare data, 65,748 patients aged 66 years or older who were diagnosed with stage I to IIIA NSCLC or stage I to III CRC from 2001 through 2009 and who underwent surgical resection were identified. Trends in "any PET" or "PET-only" use 6 to 18 months postoperatively were assessed. RESULTS:Any PET use more than doubled over the study period. Eleven percent of patients with NSCLC and 4% of those with CRC diagnosed in 2001 received any PET, compared with 25% of patients with NSCLC and 13% of those with CRC in 2009 (P < .001 for both). Higher stage disease was correlated with higher PET utilization and faster growth in use over the study period. PET-only use also increased over the study period, especially in higher stage disease. Fewer than 2% of patients diagnosed with stage IIIA NSCLC in 2001 received PET only, compared with 15% of patients diagnosed in 2009 (P = .014). Similarly, 1% of patients diagnosed with stage III CRC in 2001 received PET only, compared with 8% of patients diagnosed in 2009 (P < .001). CONCLUSIONS:PET utilization during the surveillance period increased between 2001 and 2009. Further research is needed to determine the factors driving use of surveillance PET and to examine relationships between PET and patient outcomes.