The 60% of patients at highest risk for lung cancer in the National Lung Screening Trial accounted for 88% of the lung-cancer deaths prevented by low-dose CT screening. The use of risk assessment can ...improve the yield from low-dose CT screening for lung cancer.
Lung cancer is the most common cause of cancer-related death in the United States, accounting for 28% and 26% of all cancer deaths among men and women, respectively.
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Recent results from the National Lung Screening Trial (NLST), which showed a 20% reduction in lung-cancer mortality with low-dose computed tomography (CT) screening, as compared with chest radiography, highlighted the opportunity to reduce the burden of death from lung cancer.
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With 94 million current and former smokers in the United States,
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deciding which smokers to target for low-dose CT screening remains an important public health challenge, given the potential costs and harms . . .
Leisure time physical activity reduces the risk of premature mortality, but the years of life expectancy gained at different levels remains unclear. Our objective was to determine the years of life ...gained after age 40 associated with various levels of physical activity, both overall and according to body mass index (BMI) groups, in a large pooled analysis.
We examined the association of leisure time physical activity with mortality during follow-up in pooled data from six prospective cohort studies in the National Cancer Institute Cohort Consortium, comprising 654,827 individuals, 21-90 y of age. Physical activity was categorized by metabolic equivalent hours per week (MET-h/wk). Life expectancies and years of life gained/lost were calculated using direct adjusted survival curves (for participants 40+ years of age), with 95% confidence intervals (CIs) derived by bootstrap. The study includes a median 10 y of follow-up and 82,465 deaths. A physical activity level of 0.1-3.74 MET-h/wk, equivalent to brisk walking for up to 75 min/wk, was associated with a gain of 1.8 (95% CI: 1.6-2.0) y in life expectancy relative to no leisure time activity (0 MET-h/wk). Higher levels of physical activity were associated with greater gains in life expectancy, with a gain of 4.5 (95% CI: 4.3-4.7) y at the highest level (22.5+ MET-h/wk, equivalent to brisk walking for 450+ min/wk). Substantial gains were also observed in each BMI group. In joint analyses, being active (7.5+ MET-h/wk) and normal weight (BMI 18.5-24.9) was associated with a gain of 7.2 (95% CI: 6.5-7.9) y of life compared to being inactive (0 MET-h/wk) and obese (BMI 35.0+). A limitation was that physical activity and BMI were ascertained by self report.
More leisure time physical activity was associated with longer life expectancy across a range of activity levels and BMI groups. Please see later in the article for the Editors' Summary.
Summary Background Concurrent testing for human papillomavirus (HPV) and cervical cytology (co-testing) is an approved alternative to cytology alone in women aged 30 years and older. We aimed to ...assess the safety in routine clinical practice of 3-year screening intervals for women testing negative for HPV with normal cytology and to assess if co-testing can identify women at high risk of cervical cancer or cervical intraepithelial neoplasia grade 3 (CIN3) or worse over 5 years. Methods We assessed the 5-year cumulative incidence, starting in 2003–05, of cervical cancer and CIN3 or worse for 331 818 women aged 30 years and older who enrolled in co-testing at Kaiser Permanente Northern California (Berkeley, CA, USA) and had adequate enrolment co-test results. Follow-up continued until Dec 31, 2009. We defined cumulative incidence to include prevalence at enrolment and incidence after enrolment. Prevalence at enrolment was defined as the ratio of women diagnosed with each outcome on the biopsy visit immediately after their enrolment screening visit to the total enrolled women. At screening visits only HPV test and Pap smear samples were collected, and at biopsy visits colposcopically directed biopsies were taken. To estimate post-enrolment incidence, we used Weibull survival models. Findings In 315 061 women negative by HPV testing, the 5-year cumulative incidence of cancer was 3·8 per 100 000 women per year, slightly higher than for the 306 969 who were both negative by HPV and Pap testing (3·2 per 100 000), and half the cancer risk of the 319 177 who were negative by Pap testing (7·5 per 100 000). 313 465 (99·5%) women negative by HPV testing had either normal cytology or equivocal abnormalities. Abnormal cytology greatly increased cumulative incidence of CIN3 or worse over 5 years for the 16 757 positive by HPV testing (12·1% vs 5·9%; p<0·0001). By contrast, although statistically significant, abnormal cytology did not increase 5-year risk of CIN3 or worse for women negative by HPV testing to a substantial level (0·86% vs 0·16%; p=0·004). 12 208 (73%) of the women positive by HPV testing had no cytological abnormality, and these women had 258 (35%) of 747 CIN3 or adenocarcinoma in situ, 25 (29%) of 87 cancers, and 17 (63%) of 27 adenocarcinomas. Interpretation For women aged 30 years and older in routine clinical practice who are negative by co-testing (both HPV and cytology), 3-year screening intervals were safe because a single negative test for HPV was sufficient to reassure against cervical cancer over 5 years. Incorporating HPV testing with cytology also resulted in earlier identification of women at high risk of cervical cancer, especially adenocarcinoma. Testing for HPV without adjunctive cytology might be sufficiently sensitive for primary screening for cervical cancer. Funding Intramural Research Program of the US National Cancer Institute/NIH/DHHS, and the American Cancer Society.
Selection Criteria for Lung-Cancer Screening Tammemägi, Martin C; Katki, Hormuzd A; Hocking, William G ...
The New England journal of medicine,
02/2013, Volume:
368, Issue:
8
Journal Article
Peer reviewed
Open access
Low-dose CT scanning reduces lung-cancer mortality. Further improvements are possible if the screened population includes a larger proportion of high-risk persons. The authors added features to the ...criteria for screening that improved sensitivity and positive predictive value.
The National Lung Screening Trial (NLST) showed that lung-cancer screening with the use of low-dose computed tomography (CT) resulted in a 20% reduction in mortality from lung cancer.
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Some organizations now recommend adoption of lung-cancer screening in clinical practice for high-risk persons if high-quality imaging, diagnostic methods, and treatment are available.
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–
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Most of these recommendations identify persons to be screened by applying the NLST criteria, which include an age between 55 and 74 years, a history of smoking of at least 30 pack-years, a period of less than 15 years since cessation of smoking, or some variant of these . . .
Abstract
Background
The optimal clinical management of oral precancer remains uncertain. We investigated the natural history of oral leukoplakia, the most common oral precancerous lesion, to estimate ...the relative and absolute risks of progression to cancer, the predictive accuracy of a clinician’s decision to biopsy a leukoplakia vis-à-vis progression, and histopathologic predictors of progression.
Methods
We conducted a retrospective cohort study (1996–2012) of patients with oral leukoplakia (n = 4886), identified using electronic medical records within Kaiser Permanente Northern California. Among patients with leukoplakia who received a biopsy (n = 1888), we conducted a case-cohort study to investigate histopathologic predictors of progression. Analyses included indirect standardization and unweighted or weighted Cox regression.
Results
Compared with the overall Kaiser Permanente Northern California population, oral cancer incidence was substantially elevated in oral leukoplakia patients (standardized incidence ratio = 40.8, 95% confidence interval CI = 34.8 to 47.6; n = 161 cancers over 22 582 person-years). Biopsied leukoplakias had a higher oral cancer risk compared with those that were not biopsied (adjusted hazard ratio = 2.38, 95% CI = 1.73 to 3.28). However, to identify a prevalent or incident oral cancer, the biopsy decision had low sensitivity (59.6%), low specificity (62.1%), and moderate positive–predictive value (5.1%). Risk of progression to oral cancer statistically significantly increased with the grade of dysplasia; 5-year competing risk-adjusted absolute risks were: leukoplakia overall = 3.3%, 95% CI = 2.7% to 3.9%; no dysplasia = 2.2%, 95% CI = 1.5% to 3.1%; mild-dysplasia = 11.9%, 95% CI = 7.1% to 18.1%; moderate-dysplasia = 8.7%, 95% CI = 3.2% to 17.9%; and severe dysplasia = 32.2%, 95% CI = 8.1%–60.0%. Yet 39.6% of cancers arose from biopsied leukoplakias without dysplasia.
Conclusions
The modest accuracy of the decision to biopsy a leukoplakia vis-à-vis presence or eventual development of oral cancer highlights the need for routine biopsy of all leukoplakias regardless of visual or clinical impression. Leukoplakia patients, particularly those with dysplasia, need to be closely monitored for signs of early cancer.
A property of diagnostic tests and risk models deserving more attention is risk stratification, defined as the ability of a test or model to separate those at high absolute risk of disease from those ...at low absolute risk. Risk stratification fills a gap between measures of classification (ie, area under the curve (AUC)) that do not require absolute risks and decision analysis that requires not only absolute risks but also subjective specification of costs and utilities. We introduce mean risk stratification (MRS) as the average change in risk of disease (posttest‐pretest) revealed by a diagnostic test or risk model dichotomized at a risk threshold. Mean risk stratification is particularly valuable for rare conditions, where AUC can be high but MRS can be low, identifying situations that temper overenthusiasm for screening with the new test/model. We apply MRS to the controversy over who should get testing for mutations in BRCA1/2 that cause high risks of breast and ovarian cancers. To reveal different properties of risk thresholds to refer women for BRCA1/2 testing, we propose an eclectic approach considering MRS and other metrics. The value of MRS is to interpret AUC in the context of BRCA1/2 mutation prevalence, providing a range of risk thresholds at which a risk model is “optimally informative,” and to provide insight into why net benefit arrives to its conclusion.
Lung cancer screening guidelines recommend using individualized risk models to refer ever-smokers for screening. However, different models select different screening populations. The performance of ...each model in selecting ever-smokers for screening is unknown.
To compare the U.S. screening populations selected by 9 lung cancer risk models (the Bach model; the Spitz model; the Liverpool Lung Project LLP model; the LLP Incidence Risk Model LLPi; the Hoggart model; the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Model 2012 PLCOM2012; the Pittsburgh Predictor; the Lung Cancer Risk Assessment Tool LCRAT; and the Lung Cancer Death Risk Assessment Tool LCDRAT) and to examine their predictive performance in 2 cohorts.
Population-based prospective studies.
United States.
Models selected U.S. screening populations by using data from the National Health Interview Survey from 2010 to 2012. Model performance was evaluated using data from 337 388 ever-smokers in the National Institutes of Health-AARP Diet and Health Study and 72 338 ever-smokers in the CPS-II (Cancer Prevention Study II) Nutrition Survey cohort.
Model calibration (ratio of model-predicted to observed cases expected-observed ratio) and discrimination (area under the curve AUC).
At a 5-year risk threshold of 2.0%, the models chose U.S. screening populations ranging from 7.6 million to 26 million ever-smokers. These disagreements occurred because, in both validation cohorts, 4 models (the Bach model, PLCOM2012, LCRAT, and LCDRAT) were well-calibrated (expected-observed ratio range, 0.92 to 1.12) and had higher AUCs (range, 0.75 to 0.79) than 5 models that generally overestimated risk (expected-observed ratio range, 0.83 to 3.69) and had lower AUCs (range, 0.62 to 0.75). The 4 best-performing models also had the highest sensitivity at a fixed specificity (and vice versa) and similar discrimination at a fixed risk threshold. These models showed better agreement on size of the screening population (7.6 million to 10.9 million) and achieved consensus on 73% of persons chosen.
No consensus on risk thresholds for screening.
The 9 lung cancer risk models chose widely differing U.S. screening populations. However, 4 models (the Bach model, PLCOM2012, LCRAT, and LCDRAT) most accurately predicted risk and performed best in selecting ever-smokers for screening.
Intramural Research Program of the National Institutes of Health/National Cancer Institute.
The main goal of cervical screening programs is to detect and treat precancer before cancer develops. Human papillomavirus (HPV) testing is more sensitive than cytology for detecting precancer. ...However, reports of rare HPV-negative, cytology-positive cancers are motivating continued use of both tests (cotesting) despite increased testing costs.
We quantified the detection of cervical precancer and cancer by cotesting compared with HPV testing alone at Kaiser Permanente Northern California (KPNC), where 1 208 710 women age 30 years and older have undergone triennial cervical cotesting since 2003. Screening histories preceding cervical cancers (n = 623) and precancers (n = 5369) were examined to assess the relative contribution of the cytology and HPV test components in identifying cases. The performances of HPV testing and cytology were compared using contingency table methods, general estimating equation models, and nonparametric statistics; all statistical tests were two-sided.
HPV testing identified more women subsequently diagnosed with cancer (P < .001) and precancer (P < .001) than cytology. HPV testing was statistically significantly more likely to be positive for cancer at any time point (P < .001), except within 12 months (P = .10). HPV-negative/cytology-positive results preceded only small fractions of cases of precancer (3.5%) and cancer (5.9%); these cancers were more likely to be regional or distant stage with squamous histopathology than other cases. Given the rarity of cancers among screened women, the contribution of cytology to screening translated to earlier detection of at most five cases per million women per year. Two-thirds (67.9%) of women found to have cancer during 10 years of follow-up at KPNC were detected by the first cotest performed.
The added sensitivity of cotesting vs HPV alone for detection of treatable cancer affected extremely few women.
There are well-documented disparities in lung cancer outcomes across populations. Lung cancer screening (LCS) has the potential to reduce lung cancer mortality, but for this benefit to be realized by ...all high-risk groups, there must be careful attention to ensuring equitable access to this lifesaving preventive health measure.
To outline current knowledge on disparities in eligibility criteria for, access to, and implementation of LCS, and to develop an official American Thoracic Society statement to propose strategies to optimize current screening guidelines and resource allocation for equitable LCS implementation and dissemination.
A multidisciplinary panel with expertise in LCS, implementation science, primary care, pulmonology, health behavior, smoking cessation, epidemiology, and disparities research was convened. Participants reviewed available literature on historical disparities in cancer screening and emerging evidence of disparities in LCS.
Existing LCS guidelines do not consider racial, ethnic, socioeconomic, and sex-based differences in smoking behaviors or lung cancer risk. Multiple barriers, including access to screening and cost, further contribute to the inequities in implementation and dissemination of LCS.
This statement identifies the impact of LCS eligibility criteria on vulnerable populations who are at increased risk of lung cancer but do not meet eligibility criteria for screening, as well as multiple barriers that contribute to disparities in LCS implementation. Strategies to improve the selection and dissemination of LCS in vulnerable groups are described.
IMPORTANCE: The US Preventive Services Task Force (USPSTF) recommends computed tomography (CT) lung cancer screening for ever-smokers aged 55 to 80 years who have smoked at least 30 pack-years with ...no more than 15 years since quitting. However, selecting ever-smokers for screening using individualized lung cancer risk calculations may be more effective and efficient than current USPSTF recommendations. OBJECTIVE: Comparison of modeled outcomes from risk-based CT lung-screening strategies vs USPSTF recommendations. DESIGN, SETTING, AND PARTICIPANTS: Empirical risk models for lung cancer incidence and death in the absence of CT screening using data on ever-smokers from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO; 1993-2009) control group. Covariates included age; education; sex; race; smoking intensity, duration, and quit-years; body mass index; family history of lung cancer; and self-reported emphysema. Model validation in the chest radiography groups of the PLCO and the National Lung Screening Trial (NLST; 2002-2009), with additional validation of the death model in the National Health Interview Survey (NHIS; 1997-2001), a representative sample of the United States. Models were applied to US ever-smokers aged 50 to 80 years (NHIS 2010-2012) to estimate outcomes of risk-based selection for CT lung screening, assuming screening for all ever-smokers, yield the percent changes in lung cancer detection and death observed in the NLST. EXPOSURES: Annual CT lung screening for 3 years beginning at age 50 years. MAIN OUTCOMES AND MEASURES: For model validity: calibration (number of model-predicted cases divided by number of observed cases estimated/observed) and discrimination (area under curve AUC). For modeled screening outcomes: estimated number of screen-avertable lung cancer deaths and estimated screening effectiveness (number needed to screen NNS to prevent 1 lung cancer death). RESULTS: Lung cancer incidence and death risk models were well calibrated in PLCO and NLST. The lung cancer death model calibrated and discriminated well for US ever-smokers aged 50 to 80 years (NHIS 1997-2001: estimated/observed = 0.94 95%CI, 0.84-1.05; AUC, 0.78 95%CI, 0.76-0.80). Under USPSTF recommendations, the models estimated 9.0 million US ever-smokers would qualify for lung cancer screening and 46 488 (95% CI, 43 924-49 053) lung cancer deaths were estimated as screen-avertable over 5 years (estimated NNS, 194 95% CI, 187-201). In contrast, risk-based selection screening of the same number of ever-smokers (9.0 million) at highest 5-year lung cancer risk (≥1.9%) was estimated to avert 20% more deaths (55 717 95% CI, 53 033-58 400) and was estimated to reduce the estimated NNS by 17% (NNS, 162 95% CI, 157-166). CONCLUSIONS AND RELEVANCE: Among a cohort of US ever-smokers aged 50 to 80 years, application of a risk-based model for CT screening for lung cancer compared with a model based on USPSTF recommendations was estimated to be associated with a greater number of lung cancer deaths prevented over 5 years, along with a lower NNS to prevent 1 lung cancer death.
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