Lung Screening Benefits and Challenges: A Review of The Data and Outline for Implementation

Lung cancer is the leading cause of cancer-related deaths worldwide, accounting for almost a fifth of all cancer-related deaths. Annual computed tomographic lung cancer screening (CTLS) detects lung cancer at earlier stages and reduces lung cancer-related mortality among high-risk individuals. Many medical organizations, including the U.S. Preventive Services Task Force, recommend annual CTLS in high-risk populations. However, fewer than 5% of individuals worldwide at high risk for lung cancer have undergone screening. In large part, this is owing to delayed implementation of CTLS in many countries throughout the world. Factors contributing to low uptake in countries with longstanding CTLS endorsement, such as the United States, include lack of patient and clinician awareness of current recommendations in favor of CTLS and clinician concerns about CTLS-related radiation exposure, false-positive results, overdiagnosis, and cost. This review of the literature serves to address these concerns by evaluating the potential risks and benefits of CTLS. Review of key components of a lung screening program, along with an updated shared decision aid, provides guidance for program development and optimization. Review of studies evaluating the population considered "high-risk" is included as this may affect future guidelines within the United States and other countries considering lung screening implementation

Personalising lung cancer screening

Randomised clinical trials have shown the efficacy of computed tomography lung cancer screening, initiating discussions on whether and how to implement population-based screening programs. Due to smoking behaviour being the primary risk-factor for lung cancer and part of the criteria for determining screening eligibility, lung cancer screening is inherently risk-based. In fact, the selection of high-risk individuals has been shown to be essential in implementing lung cancer screening in a cost-effective manner. Furthermore, studies have shown that further risk-stratification may improve screening efficiency, allow personalisation of the screening interval and reduce health disparities. However, implementing risk-based lung cancer screening programs also requires overcoming a num

Lung cancer screening use and implications of varying eligibility criteria by race and ethnicity: 2019 Behavioral Risk Factor Surveillance System data

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/172243/1/cncr34098.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/172243/2/cncr34098_am.pd

Additional file 1 of Risk prediction models for lung cancer in people who have never smoked: a protocol of a systematic review

Additional file 1: Table S1. PRISMA-P 2015 Checklist. Table S2. Primary literature search. Database: Ovid MEDLINE(R) and Epub Ahead of Print, InProcess, In-Data-Review & Other Non-Indexed Citations, Daily and Versions

Correction: Risk prediction models for selection of lung cancer screening candidates: A retrospective validation study.

[This corrects the article DOI: 10.1371/journal.pmed.1002277.]

Evaluation of the Lung Cancer Risks at Which to Screen Ever- and Never-Smokers: Screening Rules Applied to the PLCO and NLST Cohorts

<div><p>Background</p><p>Lung cancer risks at which individuals should be screened with computed tomography (CT) for lung cancer are undecided. This study's objectives are to identify a risk threshold for selecting individuals for screening, to compare its efficiency with the U.S. Preventive Services Task Force (USPSTF) criteria for identifying screenees, and to determine whether never-smokers should be screened. Lung cancer risks are compared between smokers aged 55–64 and ≥65–80 y.</p><p>Methods and Findings</p><p>Applying the PLCO_m2012 model, a model based on 6-y lung cancer incidence, we identified the risk threshold above which National Lung Screening Trial (NLST, <i>n = </i>53,452) CT arm lung cancer mortality rates were consistently lower than rates in the chest X-ray (CXR) arm. We evaluated the USPSTF and PLCO_m2012 risk criteria in intervention arm (CXR) smokers (<i>n = </i>37,327) of the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO). The numbers of smokers selected for screening, and the sensitivities, specificities, and positive predictive values (PPVs) for identifying lung cancers were assessed. A modified model (PLCO_all2014) evaluated risks in never-smokers. At PLCO_m2012 risk ≥0.0151, the 65th percentile of risk, the NLST CT arm mortality rates are consistently below the CXR arm's rates. The number needed to screen to prevent one lung cancer death in the 65th to 100th percentile risk group is 255 (95% CI 143 to 1,184), and in the 30th to <65th percentile risk group is 963 (95% CI 291 to −754); the number needed to screen could not be estimated in the <30th percentile risk group because of absence of lung cancer deaths. When applied to PLCO intervention arm smokers, compared to the USPSTF criteria, the PLCO_m2012 risk ≥0.0151 threshold selected 8.8% fewer individuals for screening (<i>p<</i>0.001) but identified 12.4% more lung cancers (sensitivity 80.1% [95% CI 76.8%–83.0%] versus 71.2% [95% CI 67.6%–74.6%], <i>p<</i>0.001), had fewer false-positives (specificity 66.2% [95% CI 65.7%–66.7%] versus 62.7% [95% CI 62.2%–63.1%], <i>p<</i>0.001), and had higher PPV (4.2% [95% CI 3.9%–4.6%] versus 3.4% [95% CI 3.1%–3.7%], <i>p<</i>0.001). In total, 26% of individuals selected for screening based on USPSTF criteria had risks below the threshold PLCO_m2012 risk ≥0.0151. Of PLCO former smokers with quit time >15 y, 8.5% had PLCO_m2012 risk ≥0.0151. None of 65,711 PLCO never-smokers had PLCO_m2012 risk ≥0.0151. Risks and lung cancers were significantly greater in PLCO smokers aged ≥65–80 y than in those aged 55–64 y. This study omitted cost-effectiveness analysis.</p><p>Conclusions</p><p>The USPSTF criteria for CT screening include some low-risk individuals and exclude some high-risk individuals. Use of the PLCO_m2012 risk ≥0.0151 criterion can improve screening efficiency. Currently, never-smokers should not be screened. Smokers aged ≥65–80 y are a high-risk group who may benefit from screening.</p><p><i>Please see later in the article for the Editors' Summary</i></p></div

Mortality rates, rate ratios, and rate differences in NLST participants by trial arm and by decile of PLCO_m2012 risk.

<p>PLCO_m2012 model risk decile boundaries were established in PLCO control smokers.</p><p>*Rate difference is incidence rate in CT arm per 10,000 minus incidence rate in CXR arm per 10,000. A negative absolute rate indicates a lower rate of lung cancer death in the CT arm compared to the CXR arm. PLCO_m2012 refers to the lung cancer risk prediction model described in <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1001764#pmed.1001764-Tammemgi1" target="_blank">[11]</a>.</p><p>NA, not applicable (because of zero occurring in denominator).</p><p>Mortality rates, rate ratios, and rate differences in NLST participants by trial arm and by decile of PLCO_m2012 risk.</p

PLCO_m2012-estimated risks for high-risk individuals by smoking quit time in former smokers.

<p>Estimates were prepared for white former smokers who are 68 y old, are high-school graduates, have a body mass index of 27 kg/m², have no family history of lung cancer, have no personal history of cancer, started smoking at age 14 y, and smoked on average 30 cigarettes per day. As the quit time increases, smoking duration correspondingly decreases. The dotted horizontal line indicates the PLCO_m2012 ≥0.0151 risk threshold. PLCO_m2012 refers to the lung cancer risk prediction model described in <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1001764#pmed.1001764-Tammemgi1" target="_blank">[11]</a>.</p

Comparison of PLCO_m2012 risk and incident lung cancer in age strata of PLCO smokers dichotomized at age 65 y.

<p>PLCO_m2012 refers to the model described in <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1001764#pmed.1001764-Tammemgi1" target="_blank">[11]</a>, and described in <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1001764#pmed.1001764.s004" target="_blank">Table S1</a>.</p><p>*<i>p</i>-Value for PLCO_m2012 risk was by <i>t</i>-test with unequal variance applied to natural-log-transformed risk values. <i>p</i>-Values for comparing proportions were by chi-square test.</p>†<p>Because PLCO_m2012 risk distributions are right-skewed, geometric means are presented.</p><p>Comparison of PLCO_m2012 risk and incident lung cancer in age strata of PLCO smokers dichotomized at age 65 y.</p

Distribution of PLCO_m2012 risks in PLCO ever-smokers who are USPSTF-criteria-positive or are NLST participants.

<p>The vertical line indicates the PLCO_m2012 risk ≥0.0151 threshold. The graph is right-truncated. PLCO_m2012 is the lung cancer risk prediction model described in <a href="http://www.plosmedicine.org/article/info:doi/10.1371/journal.pmed.1001764#pmed.1001764-Tammemgi1" target="_blank">[11]</a>.</p