You are seeing this message because your Web browser does not support basic Web standards. Find out more about why this message is appearing and what you can do to make your experience on this site better.


ABOUT JAMA
Advanced Search

Welcome   | My Account | E-mail Alerts | Access Rights | Sign In


  Vol. 297 No. 9, March 7, 2007 TABLE OF CONTENTS
  JAMA
  •  Online Features
  Original Contribution
 This Article
 •Abstract
 •PDF
 •Author in the Room Audio
 •Correction
 •Send to a friend
 • Save in My Folder
 •Save to citation manager
 •Permissions
 Citing Articles
 •Citation map
 •Citing articles on HighWire
 •Citing articles on Web of Science (148)
 •Contact me when this article is cited
 Related Content
 •Related letters
 •Related articles
 •Similar articles in JAMA
 Topic Collections
 •Oncology
 •Lung Cancer
 •Pulmonary Diseases
 •Pulmonary Diseases, Other
 •Radiologic Imaging
 •Prognosis/ Outcomes
 •Screening
 •Computed Tomography
 •Alert me on articles by topic
 Social Bookmarking
  Add to CiteULike Add to Connotea Add to Del.icio.us Add to Digg Add to Reddit Add to Technorati Add to Twitter What's this?

Computed Tomography Screening and Lung Cancer Outcomes

Peter B. Bach, MD, MAPP; James R. Jett, MD; Ugo Pastorino, MD; Melvyn S. Tockman, MD, PhD; Stephen J. Swensen, MD, MMM; Colin B. Begg, PhD

JAMA. 2007;297:953-961.

ABSTRACT

Context  Current and former smokers are currently being screened for lung cancer with computed tomography (CT), although there are limited data on the effect screening has on lung cancer outcomes. Randomized controlled trials assessing CT screening are currently under way.

Objective  To assess whether screening may increase the frequency of lung cancer diagnosis and lung cancer resection or may reduce the risk of a diagnosis of advanced lung cancer or death from lung cancer.

Design, Setting, and Participants  Longitudinal analysis of 3246 asymptomatic current or former smokers screened for lung cancer beginning in 1998 either at 1 of 2 academic medical centers in the United States or an academic medical center in Italy with follow-up for a median of 3.9 years.

Intervention  Annual CT scans with comprehensive evaluation and treatment of detected nodules.

Main Outcome Measures  Comparison of predicted with observed number of new lung cancer cases, lung cancer resections, advanced lung cancer cases, and deaths from lung cancer.

Results  There were 144 individuals diagnosed with lung cancer compared with 44.5 expected cases (relative risk [RR], 3.2; 95% confidence interval [CI], 2.7-3.8; P<.001). There were 109 individuals who had a lung resection compared with 10.9 expected cases (RR, 10.0; 95% CI, 8.2-11.9; P<.001). There was no evidence of a decline in the number of diagnoses of advanced lung cancers (42 individuals compared with 33.4 expected cases) or deaths from lung cancer (38 deaths due to lung cancer observed and 38.8 expected; RR, 1.0; 95% CI, 0.7-1.3; P = .90).

Conclusions  Screening for lung cancer with low-dose CT may increase the rate of lung cancer diagnosis and treatment, but may not meaningfully reduce the risk of advanced lung cancer or death from lung cancer. Until more conclusive data are available, asymptomatic individuals should not be screened outside of clinical research studies that have a reasonable likelihood of further clarifying the potential benefits and risks.



INTRODUCTION
 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

Lung cancer accounts for 20% of cancer deaths in Italy and 25% of cancer deaths in the United States, and 6% of all deaths in both countries.1-2 Screening individuals at high risk for lung cancer might reduce these statistics based on the premise that most cases of lung cancer that will cause death can be detected through routine screening while they are still localized and potentially curable. However, prior randomized studies of lung cancer screening with chest x-ray have not supported this premise. Rather, chest x-ray was effective at identifying many additional small tumors in the lung that could be removed, but their discovery and removal did not reduce the likelihood that individuals would be diagnosed with new cases of advanced lung cancer, or would die of lung cancer.3-7 These findings led to speculation that the additional small cancers that were being found through screening may be indolent, relative to lung cancer that is typically encountered in a clinical setting.8-9

Today there is renewed enthusiasm for lung cancer screening with computed tomography (CT) because it is more sensitive for the detection of very small nodules.10-11 Yet, CT screening depends on the same unproven premise as chest x-ray screening.

We studied the effect of CT screening on individuals enrolled in 1 of 3 single-arm studies of screening by comparing the frequency of lung cancer cases, lung cancer resection, advanced lung cancer cases, and deaths from lung cancer occurring in these studies with what would have occurred in the absence of screening, as determined from a set of validated prediction models.12-15 We aimed to produce preliminary estimates of the impact of widespread CT screening on these lung cancer outcomes.


METHODS
 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

Individuals were enrolled in 1 of 3 studies conducted at the Istituto Tumori in Milan, Italy, the Mayo Clinic in Rochester, Minn, and the Moffitt Cancer Center in Tampa, Fla.16-20 Each study recruited individuals with a smoking history and no prior history or symptoms suggestive of lung cancer through advertisements, direct mail, and local physician outreach. The Istituto Tumori study is ongoing, the Mayo Clinic study offered an initial and 3 subsequent annual CT scans, and the Moffitt study offered an initial and 4 subsequent annual CT scans. In these studies, when noncalcified nodules were detected, they were evaluated using a systematic approach of follow-up imaging and biopsy.16-17

Prediction Models

The frequency of lung cancer events occurring among the study participants was compared with benchmarks that were determined using 2 models developed to estimate an individual's level of risk of either being diagnosed with lung cancer or dying of lung cancer. Both models have been extensively described and validated in prior studies.12-15 The models were designed to apply to high-risk individuals, whose risk factor values fall within the following ranges: age 50 to 80 years, smoked for between 25 and 60 years, averaged between 10 and 60 cigarettes per day, and if quit, had quit within the past 20 years. These limits led us to exclude 58 of the 1035 individuals from the Istituto Tumori study, 81 of 1520 individuals from the Mayo Clinic study, and 321 of 1151 individuals from the Moffitt study.

Modifications of Prediction Models

The probabilities of advanced lung cancer diagnosis and lung cancer surgery were based on the estimated probability of lung cancer diagnosis from our model multiplied by the conditional probability of these events among age- and sex-matched individuals diagnosed with lung cancer in the National Cancer Institute's Surveillance, Epidemiology, and End Results cancer registry database for 1993 through 1998. Estimates for the Moffitt study were also adjusted to compensate for an enriched prevalence of obstructive lung disease (due to a requirement that participants have obstructive lung disease) in the first cohort (enrolled between December 11, 1998, and January 4, 2001; n = 376), and subsequent dilution of the prevalence of obstructive lung disease (resulting from late entry of individuals without obstructive lung disease who were not eligible for the first cohort) in the second cohort (enrolled between January 5, 2001, and August 13, 2003; n = 458). The estimated risk of each individual was multiplied by the aggregate change in the population risk resulting from the alteration in prevalence of obstructive lung disease based on the following prevalences for obstructive lung disease: 97% for cohort 1 and 25% for cohort 2. The expected prevalence in the absence of the additional entry criterion was 46%, as estimated for the 163 individuals who were newly recruited to the second cohort. The relative risk (RR) estimates for the impact of obstructive lung disease on lung cancer incidence (2.80) and lung cancer death (2.02) were taken from the literature, the latter being an average of the additional risks conferred by differing levels of obstruction, weighted by the proportion of individuals with those differing levels of obstruction in the first cohort.21-22 The end result of these adjustments was a small increase in the expected number of events.

Outcomes

We evaluated the number of individuals diagnosed with lung cancer (first diagnoses of non–small cell or small cell lung cancer), the number of first surgical resections of lung cancer, the number of individuals whose first lung cancer diagnosis was of advanced stage (stage III or IV non–small cell lung cancer or any stage of small cell lung cancer), and the number of individuals who died from lung cancer. For the Istituto Tumori study, dates and cause of death were ascertained through medical record review and the Lombardy Region cancer registry and death records, and clinician investigators coded cause of death. For the Mayo Clinic and Moffitt studies, dates and cause of death were coded according to the National Death Index assignment of cause of death to parallel other studies of lung cancer screening.8 Individuals whose vital status could not be reliably checked through public data sources were eliminated from the mortality analyses, as was the case for 1 individual enrolled in the Istituto Tumori study who resided outside of the Lombardy region of Italy, and 7 and 22 individuals enrolled in the Mayo Clinic and Moffitt studies, respectively, who did not provide Social Security numbers at the time of study enrollment.

Clinical End Points

The date of the first CT screen is the baseline for all of our analyses. The timing of lung cancer diagnoses corresponds to either the date of lung cancer in the diagnostic pathology report or the date of death for individuals who died from lung cancer without a known antecedent diagnosis. This approach to ascertaining the date of cancer diagnosis parallels the manner in which epidemiological and clinical data are collected, and thus is appropriate for the comparisons presented herein. An alternative would be to back-date the date of diagnosis to the date of the first scan on which the cancer was theoretically visible (eg, prevalence or incidence scan). Follow-up times for diagnostic and treatment end points for each individual extend to the point that the individual was diagnosed with lung cancer, or underwent surgery for lung cancer, or alternatively was lost to follow-up or died. Few individuals were lost to follow-up during the first years of the studies (89% follow-up through 2 years, 71% follow-up through 3 years), but the median follow-up was 3.9 years and only 33% were followed up past 4 years.

There is a potential that our results are biased if the probability that an individual is lost to follow-up is correlated with the likelihood that he/she experienced one of the study events. For instance, if individuals with symptoms of late-stage cancer are more likely to remain in clinical follow-up than individuals who feel healthy, such a bias would produce results that downplay the effect of CT screening on preventing advanced cancers, while the alternative would exaggerate the effect of CT screening on preventing advanced diagnosis. Given this potential source of bias, additional analyses are presented that reflect how many events would have been estimated had all individuals been followed up to the time of their observed event, or otherwise followed up to the maximum time possible, which was set to be the last date of observed follow-up for any individual in the study. These alternative analyses increase the number of predicted events without increasing the number of observed events, so they represent the most conservative estimate of the extent to which CT screening may increase the likelihood of lung cancer diagnosis, and lung cancer surgery, as well as the most optimistic projection of the extent to which CT may reduce the frequency of advanced cancer diagnosis.

Mortality and Survival End Points

For the Istituto Tumori study, the censoring date was the date of death from a cause other than lung cancer, or the date of last confirmation of vital status; for the Moffitt and Mayo Clinic studies, the censoring date was the earlier of either the date of death from a cause other than lung cancer or Decemer 31, 2004, the most recent date through which National Death Index data linked to death certificate information were complete. Our original analytic plan was to examine all deaths from lung cancer beginning at the commencement of screening but there was strong evidence for a healthy volunteer bias in the 3 studies. There was only 1 death from lung cancer occurring in the first year across all studies (compared with 9.5 deaths anticipated in the absence of screening). Because it is plausible that there was a large reduction in the first year due to the requirement that all study individuals be asymptomatic at the time of enrollment in the studies, and not plausible that CT screening reduced deaths immediately, the mortality end point was evaluated commencing 1 year after the first CT scan through death due to lung cancer or a censoring event. How the results would have appeared had the first year's events been considered is also reported. The date of tissue diagnosis served as the start time for the survival analyses.

Statistical Analysis

The numbers of observed O events were compared with the numbers expected E at the end of available follow-up time using the formula (O-E)2/E, which produces a {chi}2 statistic with 1 degree of freedom. The results are indistinguishable from those obtained from a more computationally intensive approach to calculate the variance of E.13 The 95% confidence intervals (CIs) assume a Poisson distribution. The survival estimates are based on the Kaplan-Meier method. All P values are 2-sided. P<.05 was considered statistically significant. Analyses were performed using Stata version 9.0 (StataCorp, College Station, Tex).

The study was approved by the institutional review boards of the 3 study sites where the screening was performed and written informed consent was obtained. The institutional review board at Memorial Sloan-Kettering Cancer Center acknowledged the authority of these institutions to authorize this research. Only the investigators at Memorial Sloan-Kettering Cancer Center had access to data from all 3 sites, which had been deidentified.


RESULTS
 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

Characteristics of Studies

The Mayo Clinic study contributed both the largest number of individuals and the greatest amount of follow-up time, followed by the Istituto Tumori study (Table 1). The lung cancer mortality rate overall was 3.5 lung cancer deaths per 1000 person-years; the 5.6 lung cancer deaths per 1000 person-years in the Moffitt study is most likely due to the additional prevalence of obstructive lung disease. The lung cancer mortality rates in the Istituto Tumori and Mayo Clinic cohorts (2.7 and 3.1 per 1000 person-years, respectively) are similar to the rates in prior well-known studies of lung cancer screening with chest x-ray (3.0 and 3.2 per 1000 person-years in the 2 arms of the original Mayo Clinic study; 2.6 and 3.6 per 1000 person-years in the 2 arms of a study of chest x-ray screening performed in Czechoslovakia; and 2.7 per 1000 person-years in the Memorial Sloan-Kettering study).7-9,23


View this table:
[in this window]
[in a new window]
[as a PowerPoint slide]
 
Table 1. Characteristics of Studies Included in Analysis of Computed Tomography Screening for Lung Cancer*


Frequency of Lung Cancer Diagnosis and Lung Cancer Resection

Individuals in all 3 studies were diagnosed with lung cancer in far greater numbers than would have occurred in the absence of screening (Figure 1A, B, C and Table 2). For the Istituto Tumori study, the observed frequency was 36 compared with an expected frequency of 11.3; Mayo Clinic, 66 vs 19.5; and Moffitt, 42 vs 13.7 (P<.001 for each). The number of lung cancer surgeries performed exceeded the number expected in the absence of screening to an even greater extent for the Istituto Tumori study (33 vs 2.7); Mayo Clinic (48 vs 4.8); and Moffitt (28 vs 3.4) (P<.001 for each; Figure 1D, E, F and Table 2). Combining data from the 3 studies, there were 144 cases of lung cancer diagnosed, whereas 44.5 cases were expected, which resulted in an RR of lung cancer diagnosis of 3.2 (95% CI, 2.7-3.8; P<.001; Figure 2A). A total of 109 lung cancer surgeries were performed compared with 10.9 cases expected, which resulted in an RR of lung cancer surgery of 10.0 (95% CI, 8.2-11.9; P<.001; Figure 2B). If follow-up time is included for those patients who were lost to follow-up for unknown reasons, the number of observed lung cancer cases is 2.3 times the number predicted (144 vs 62.2 predicted; P<.001) and the number of lung cancer surgeries performed is 7.2 times the number predicted (109 vs 15.2 predicted; P<.001).


Figure 1
View larger version (92K):
[in this window]
[in a new window]
[as a PowerPoint slide]
 
Figure 1. Results for Studies of Lung Cancer Screening With Computed Tomography

Conducted at the Istituto Tumori (Milan, Italy), the Mayo Clinic (Rochester, Minn), and the Moffitt Cancer Center (Tampa, Fla). The left axis shows the actual and predicted numbers of individuals with different lung cancer outcomes. The right axis shows the number at risk (blue tinted area). P values are for the difference between the observed and the predicted number of events over the course of the study.



View this table:
[in this window]
[in a new window]
[as a PowerPoint slide]
 
Table 2. Frequency of Predicted and Observed Events



Figure 2
View larger version (71K):
[in this window]
[in a new window]
[as a PowerPoint slide]
 
Figure 2. Combined Results for the Studies of Lung Cancer Screening With Computed Tomography

Conducted at the Istituto Tumori (Milan, Italy), the Mayo Clinic (Rochester, Minn), and the Moffitt Cancer Center (Tampa, Fla). The left axis shows the actual and predicted numbers of individuals with different lung cancer outcomes. The right axis shows the number at risk (blue tinted area). P values are for the difference between the observed and the predicted number of events over the course of the study.


Number of Advanced Lung Cancers and Deaths Due to Lung Cancer

Early detection via CT screening did not appear to reduce the risk of advanced lung cancer diagnoses (Figure 1G, H, I, Figure 2C, and Table 2). Combined, there were 42 cases of advanced lung cancer, while the model predicted 33.4 (P = .14). If we include the follow-up times of patients lost to follow-up for unknown reasons, providing an upper bound of possible benefit, the number of observed cases of advanced lung cancer is less than the number predicted by 18% (42 observed vs 51.2 predicted; P = .18).

There was no evidence that CT screening reduced the risk of death due to lung cancer in any of the studies individually or combined (Figure 1J, K, L, Figure 2D, and Table 2). Loss to follow-up is unlikely to have biased this outcome, which was assessed using a standardized follow-up time. Combined, there were 38 deaths due to lung cancer after the first year of screening and the model predicted 38.8 deaths (RR, 1.0; 95% CI, 0.7-1.3; P = .90). If we had included the first year of mortality data in this analysis (Table 2), CT screening would have appeared to reduce lung cancer mortality by 20%, although this reduction would not have been statistically significant (RR, 0.8; 95% CI, 0.55-1.06; P = .18).

Relationship Between Initial Lung Cancer Diagnosis and Death Due to Lung Cancer

Shown in Table 3 are the lung cancers detected during the course of the study, the number of individuals who died from lung cancer after 1 year or more of study participation who had each type of lung cancer diagnosis, and the 2-year probability of overall survival for those individuals diagnosed with lung cancer. As in other studies of CT screening, the preponderance of lung cancers (96 [67%] of 144) were of early stage (ie, stage I or stage II), and the outcomes for these individuals were quite good—only 12 (13%) of the individuals with early stage non–small cell lung cancer died from lung cancer during the study. Instead, the majority of individuals who died from lung cancer, despite participation in annual screening, did not have their cancer detected when it was in an early stage and likely to be curable: 13 (34%) of those who died from lung cancer were initially diagnosed with stage III or stage IV non–small cell lung cancer, 7 (18%) were diagnosed with small cell lung cancer, and 6 (16%) had no documented diagnosis of lung cancer prior to their death from lung cancer.


View this table:
[in this window]
[in a new window]
[as a PowerPoint slide]
 
Table 3. Lung Cancers and Lung Cancer Deaths


Reported in Table 3 are also the 2-year overall survival probabilities for each group of individuals by initial diagnosis. For instance, individuals diagnosed with stage I to stage II and stage III to stage IV non–small cell lung cancer had 2-year overall survival rates of 90% and 47%, respectively, superior to the published survival rates of 86% (stage IA) to 56% (stage IIB) in the first case, and 40% (stage IIIA) to 5% (stage IV) in the second case.24 The 4-year lung cancer–specific survival of the 81 individuals in our studies diagnosed with clinical stage I lung cancer and undergoing surgery was 94% (95% CI, 85%-97%), matching outcomes reported in another recent study of CT screening.25


COMMENT
 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

Previous studies of chest x-ray screening for lung cancer produced 2 intriguing results. Screening increased the rate of detection of small resectable lung cancers and thus the frequency of lung surgery. However, screening did not reduce the risk of either advanced lung cancer diagnosis or death from lung cancer.7 In our study of CT screening, we observed a similar pattern. When individuals are screened for lung cancer with CT, the likelihood that they are diagnosed with lung cancer is increased more than 3-fold, and the likelihood that they undergo a thoracic resection for lung cancer is increased 10-fold. However, as for chest x-ray screening, there appears to be neither a meaningful reduction in the number of advanced cancers being diagnosed nor a reduction in the number of individuals who die of lung cancer. These findings, because they are thematically consistent with the findings of several randomized studies of lung cancer screening with chest x-ray, should raise doubts about the premise underpinning CT screening for lung cancer, and also raise concerns about its potential harms if pursued on a wide scale.

To generate our findings, we used a comparative approach similar to that used in evaluations of other cancer screening tests. Cytological cervical cancer screening was established through comparisons of the incidence and mortality rates between populations in which cervical cytology screening was common compared with populations in which it was uncommon.26-28 Colonoscopy screening for colon cancer is widely recommended based on comparisons of colon cancer rates among individuals screened with colonoscopy compared with those not screened.29-31 Screening children for neuroblastoma is not recommended due to the absence of a difference in advanced cases and deaths due to neuroblastoma between screened and unscreened populations.32-33

There are 2 differences between our analyses and these other comparative studies. First, these other studies were large and definitive, while ours is small and preliminary. Second, rates of cancer events were compared between unscreened and screened populations in these other studies, while in our analyses the comparator was generated by prediction models that used individual risk factor information to estimate individual-level risk. So the validity of our comparisons hinges on our models, which in prior analyses have been shown to accurately predict the frequency of lung cancer events occurring among individuals enrolled in other screening and prevention studies.12-15

A possible explanation for the association of screening and an increase in the frequency of lung cancer diagnosis more than 3-fold is that many of the early lung cancers found through screening would not have progressed rapidly to a point of clinical detection. As such, if left unattended, they would have been unlikely to account for a meaningful share of all deaths occurring from lung cancer among the screened individuals.34-36 An alternative perspective is that the additional cancers found at screening would have progressed if left untreated to cause clinically significant disease, and ultimately death in a substantial proportion of cases.37-39 If there were a reduction in lung cancer mortality observed over a longer period of follow-up, such a finding would support this latter explanation.

Our data more strongly support the former explanation because of 2 findings. (1) The number of excess cases diagnosed each year continues to exceed the number predicted. An initial rise followed by a return to the baseline incidence rate would be more consistent with a 1-time discovery of a large number of cancers that would have soon appeared sporadically had screening not been performed. This persistent elevation of lung cancer incidence suggests that there is a pool of small nodules being found by CT screening that either have reduced metastatic potential, or have a much slower growth rate and longer natural history than that of the clinically detected lung cancers on which current knowledge of this disease is based. (2) There was no decline in the number of advanced cancers being detected in the studies. Had there been, this too would have constituted evidence that the additional cancers found through screening would have soon progressed had they not been detected. Even with our most conservative estimate, 9 fewer cases of advanced lung cancer than anticipated were observed over the entire study period across all 3 studies, which is less than one tenth the number of excess cases of lung cancer detected by screening, totaling 99.

Our finding of a 10-fold increase in lung cancer surgeries resulting from screening underscores one of the potential public health consequences of CT screening. If the majority of excess early cancers found through screening are unlikely to progress rapidly to a point where they cause clinically significant disease or death, then the thoracic surgeries performed to remove them may be insufficiently beneficial to justify the resulting morbidities. Despite some studies that have demonstrated excellent outcomes when lung cancer resections are performed in high-volume hospitals by thoracic surgeons, excellent outcomes are not uniform.38-39 Rather, the postoperative mortality rate following resection of lung cancer in the United States averages 5%, and the frequency of serious complications ranges from 20% to 44%.40-43 We did not examine the additional morbidities that result from diagnostic procedures or biopsies performed in response to an abnormal CT result, but other investigators have reported that up to 12% of people who are screened for lung cancer with CT undergo invasive biopsies that ultimately reveal 1 or more benign processes.44 Thus, these biopsies and the other diagnostic procedures that are performed in response to findings on a screening CT constitute another potential downstream harm that could result from widespread CT screening.

Our findings that CT screening is not associated with a reduction in the chance that a person will develop advanced lung cancer or die from lung cancer are important negative results that should influence how screening is viewed up until that time when more rigorous data are available from randomized trials. Our findings also emphasize the potentially confusing nature of survival analyses in screening studies. The individuals in our study with early lung cancer had excellent lung cancer–specific survival, equivalent to that reported by the International Early Lung Cancer Action Project.25 However, as our study illustrates, excellent survival of a few individuals does not necessarily equate to a benefit overall.

The mechanism responsible for the disconnect between the excellent lung cancer–specific survival observed among the few individuals with early stage cancer found by screening and the unchanged lung cancer mortality seen in the group as a whole is illustrated in Table 3. Few of the individuals who died from lung cancer in our study also belonged to the group who had their lung cancers discovered at an early stage. Instead, despite routine screening, most of the lung cancers that were ultimately fatal were not detected until an advanced stage, or until they caused death. So, although excellent survival of individuals with early stage lung cancer is a necessary condition for CT screening to be beneficial, it is not a sufficient condition. Computed tomography screening must also intercept at an early stage those cancers that will later progress to cause clinical disease and death, and in our study, CT screening did not intercept these cancers. Had it, then the number of deaths from lung cancer would have been lower than the number that we expected. In other words, our results raise further doubts about the premise of lung cancer screening, suggesting that it may be difficult to detect at an early stage a meaningful proportion of the lung cancers that cause clinically significant disease and death, even when using a sensitive technology such as CT.

These findings must be viewed in consideration of our study's limitations. A larger sample size may have allowed us to detect a benefit of screening; our 95% CIs actually allow for a reduction in lung cancer mortality as large as 30%, which would constitute a potentially important public health benefit. Also, a longer period of follow-up, or a longer period of screening, may have allowed us to detect a benefit of screening. The design of the National Lung Screening Trial of CT is germane to this latter concern because the duration of screening and length of follow-up roughly match those in our study. In the National Lung Screening Trial, individuals will be screened 3 times (at baseline and at 2 annual follow-up appointments). All 3 of our studies included at least this many screening evaluations. The National Lung Screening Trial is then powered to detect a 50% reduction in lung cancer mortality within about 2 years of follow-up, and a 20% reduction in mortality within 6 years of the commencement of screening.45 In our study, the median amount of follow-up from the initial CT evaluation to the mortality end point was nearly 5 years.

Despite the paucity of evidence supporting lung cancer screening, and no clear delineation of the harms that may result from excess diagnoses, additional diagnostic procedures, and additional treatment, screening is being offered widely, and claims that screening saves lives and should be available to all are widespread.25, 46-47 Legislation has also been introduced that would require Medicare to cover lung cancer screening.48 A more prudent course would be to await the findings of the National Lung Screening Trial and several trials that are being conducted and planned in Europe. It would also be wise to explore other approaches to lung cancer prevention and early detection based on modalities other than regular imaging. Until then, CT screening for lung cancer should be considered an experimental procedure, based on an uncorroborated premise.


AUTHOR INFORMATION
 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

Corresponding Author: Peter B. Bach, MD, MAPP, Memorial Sloan-Kettering Cancer Center, Box 221, New York, NY 10021.

Author Contributions: Drs Bach and Begg had full access to the combined, deidentified data, and take responsibility for the integrity of the data analysis, which they performed.

Study concept and design: Bach, Jett, Pastorino.

Acquisition of data: Jett, Pastorino, Tockman, Swensen.

Analysis and interpretation of data: Bach, Pastorino, Tockman, Swensen, Begg.

Drafting of the manuscript: Bach, Begg.

Critical revision of the manuscript for important intellectual content: Bach, Jett, Pastorino, Tockman, Swensen, Begg.

Statistical analysis: Bach, Pastorino, Begg.

Obtained funding: Bach, Tockman.

Administrative, technical, or material support: Bach, Jett, Tockman.

Study supervision: Bach, Pastorino, Tockman.

Financial Disclosures: None reported.

Funding/Support: The pooling and secondary analysis of data from the 3 study sites, and the death record searches, were supported by institutional funds at the 4 involved institutions, and also by the Steps for Breath fund at Memorial Sloan-Kettering Cancer Center. The original data collection at the 3 sites was supported by the European Institute of Oncology and the Italian Ministry of Health (Istituto Tumori); the National Cancer Institute (grant R01CA79935) (Mayo Clinic study); the Department of Defense (Army Advanced Cancer Detection grant DAMD17-98-1-8659) and the National Cancer Institute (grant UO1CA94973) (Moffitt study).

Role of Sponsors: None of the sponsors played any role in the design and conduct of this study; the collection, management, analysis, and interpretation of the data; or the preparation, review, or approval of the manuscript.

Acknowledgment: We are indebted to the study participants and study investigators of the Beta Carotene and Retinol Efficacy Trial (CARET) trial and the computed tomography screening studies conducted at the Mayo Clinic, the Moffitt Cancer Center, and the Istituto Tumori, as well as to our many colleagues who offered useful insights during this project, none of whom received compensation for our study. We are also indebted to several individuals who were employed at the study sites: Jacqueline Rehbein and Aaron Bungum at the Mayo Clinic (Rochester, Minn); John Bomba at the Moffitt Cancer Center (Tampa, Fla); and Morgan Hanger at Memorial Sloan-Kettering Cancer Center (New York, NY). We also are grateful to Robert Bilgrad, MA, MPH, at the National Center for Health Statistics (Hyattsville, Md), for his assistance but who was not compensated for his work.

Author Affiliations: Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (Drs Bach and Begg); Division of Pulmonary Medicine and Oncology (Dr Jett), Department of Radiology (Dr Swensen), Mayo Clinic, Rochester, Minn; Division of Thoracic Surgery, Istituto Tumori, Milan, Italy (Dr Pastorino); and Department of Cancer Prevention and Control, Moffitt Cancer Center, Tampa, Fla (Dr Tockman).


REFERENCES
 Jump to Section
 •Top
 •Introduction
 •Methods
 •Results
 •Comment
 •Author information
 •References

1. Jemal A, Clegg LX, Ward E, et al. Annual report to the nation on the status of cancer, 1975-2001, with a special feature regarding survival. Cancer. 2004;101:3-27. FULL TEXT | WEB OF SCIENCE | PUBMED
2. World Health Organization. Numbers and Rates of Registered Deaths: Italy, 2001. Geneva, Switzerland: World Health Organization; 2002.
3. Fontana R, Sanderson DR, Woolner LB, Taylor WF, Miller WE, Muhm JR. Lung cancer screening: the Mayo program. J Occup Med. 1986;28:746-750. WEB OF SCIENCE | PUBMED
4. Kubik A, Polak J. Lung cancer detection: results of a randomized prospective study in Czechoslovakia. Cancer. 1986;57:2427-2437. FULL TEXT | WEB OF SCIENCE | PUBMED
5. Levin ML, Tockman MS, Frost JK, Ball WC Jr. Lung cancer mortality in males screened by chest X-ray and cytologic sputum examination: a preliminary report. Recent Results Cancer Res. 1982;82:138-146. WEB OF SCIENCE | PUBMED
6. Stitik FP, Tockman MS. Radiographic screening in the early detection of lung cancer. Radiol Clin North Am. 1978;16:347-366. WEB OF SCIENCE | PUBMED
7. Bach PB, Kelley MJ, Tate RC, McCrory DC. Screening for lung cancer: a review of the current literature. Chest. 2003;123(suppl):72S-82S. FREE FULL TEXT
8. Marcus PM, Bergstralh EJ, Fagerstrom RM, et al. Lung cancer mortality in the Mayo Lung Project: impact of extended follow-up. J Natl Cancer Inst. 2000;92:1308-1316. FREE FULL TEXT
9. Kubik AK, Parkin DM, Zatloukal P. Czech Study on Lung Cancer Screening: post-trial follow-up of lung cancer deaths up to year 15 since enrollment. Cancer. 2000;89(suppl):2363-2368. FULL TEXT | WEB OF SCIENCE | PUBMED
10. Henschke CI, McCauley DI, Yankelevitz DF, et al. Early lung cancer action project: a summary of the findings on baseline screening. Oncologist. 1901;6:147-152.
11. Sone S, Takashima S, Li F, et al. Mass screening for lung cancer with mobile spiral computed tomography scanner. Lancet. 1998;351:1242-1245. FULL TEXT | WEB OF SCIENCE | PUBMED
12. Bach PB, Kattan MW, Thornquist MD, et al. Variations in lung cancer risk among smokers. J Natl Cancer Inst. 2003;95:470-478. FREE FULL TEXT
13. Bach PB, Elkin EB, Pastorino U, et al. Benchmarking lung cancer mortality rates in current and former smokers. Chest. 2004;126:1742-1749. FREE FULL TEXT
14. Bach PB, Begg CB. Further validation of lung cancer mortality model [published online March 18, 2005]. Chest. http://www.chestjournal.org/cgi/eletters/126/6/1742. Accessibility verified February 7, 2007.
15. Cronin K, Gail MH, Zou Z, Bach PB, Virtamo J, Albanes D. Validation of a model of lung cancer risk prediction among smokers. J Natl Cancer Inst. 2006;98:637-640. FREE FULL TEXT
16. Pastorino U, Bellomi M, Landoni C, et al. Early lung-cancer detection with spiral CT and positron emission tomography in heavy smokers: 2-year results. Lancet. 2003;362:593-597. FULL TEXT | WEB OF SCIENCE | PUBMED
17. Swensen SJ, Jett JR, Sloan JA, et al. Screening for lung cancer with low-dose spiral computed tomography. Am J Respir Crit Care Med. 2002;165:508-513. FREE FULL TEXT
18. Swensen SJ, Jett JR, Hartman TE, et al. Lung cancer screening with CT: Mayo Clinic experience. Radiology. 2003;226:756-761. FREE FULL TEXT
19. Zhukov TA, Johanson RA, Cantor AB, Clark RA, Tockman MS. Discovery of distinct protein profiles specific for lung tumors and pre-malignant lung lesions by SELDI mass spectrometry. Lung Cancer. 2003;40:267-279. WEB OF SCIENCE | PUBMED
20. Tockman MS, Hazelton T, Coppage L, et al. Lung cancer screening with helical CT: evidence for a stage shift. Presented at: 10th International Congress on Lung Cancer; August 10-14, 2003; Vancouver, British Columbia.
21. Mannino DM, Aguayo SM, Petty TL, Redd SC. Low lung function and incident lung cancer in the United States: data From the First National Health and Nutrition Examination Survey follow-up. Arch Intern Med. 2003;163:1475-1480. FREE FULL TEXT
22. Lange P, Nyboe J, Appleyard M, Jensen G, Schnohr P. Relation of ventilatory impairment and of chronic mucus hypersecretion to mortality from obstructive lung disease and from all causes. Thorax. 1990;45:579-585. FREE FULL TEXT
23. Melamed MR. Lung cancer screening results in the National Cancer Institute New York study. Cancer. 2000;89(suppl):2356-2362. FULL TEXT | WEB OF SCIENCE | PUBMED
24. Mountain CF. Revisions in the international system for staging lung cancer. Chest. 1997;111:1710-1717. FREE FULL TEXT
25. Henschke CI, Yankelevitz DF, Libby DM, Pasmantier MW, Smith JP, Miettinen OS. Survival of patients with stage I lung cancer detected on CT screening. N Engl J Med. 2006;355:1763-1771. FREE FULL TEXT
26. Gibson L, Spiegelhalter DJ, Camilleri-Ferranti C, Day NE. Trends in invasive cervical cancer incidence in East Anglia from 1971-1993. J Med Screen. 1997;4:44-48. PUBMED
27. Kjellgren O. Mass screening in Sweden for cancer of the uterine cervix: effect on incidence and mortality. Gynecol Obstet Invest. 1986;22:57-63. WEB OF SCIENCE | PUBMED
28. Hakama M, Chamberlain J, Day NE, Miller AB, Prorok PC. Evaluation of screening programs for gynecological cancers. Br J Cancer. 1985;52:669-673. WEB OF SCIENCE | PUBMED
29. Winawer SJ, Zauber AG, Ho MN, et al, The National Polyp Study Workgroup. Prevention of colorectal cancer by colonoscopic polypectomy. N Engl J Med. 1993;329:1977-1981. FREE FULL TEXT
30. Lieberman DA, Weiss DG, Bond JH, Ahnen DJ, Garewal H, Chejfec G, Veterans Affairs Cooperative Study Group 380. Use of colonoscopy to screen asymptomatic adults for colorectal cancer. N Engl J Med. 2000;343:162-168. FREE FULL TEXT
31. Thiis-Evensen E, Hoff GS, Sauar J, Langmark F, Majak BM, Vatn MH. Population-based surveillance by colonoscopy: effect on the incidence of colorectal cancer: Telemark Polyp Study I. Scand J Gastroenterol. 1999;34:414-420. FULL TEXT | WEB OF SCIENCE | PUBMED
32. Woods WG, Gao RN, Shuster JJ, et al. Screening of infants and mortality due to neuroblastoma. N Engl J Med. 2002;346:1041-1046. FREE FULL TEXT
33. Schilling FH, Spix C, Berthold F, et al. Neuroblastoma screening at one year of age. N Engl J Med. 2002;346:1047-1053. FREE FULL TEXT
34. Black WC. Overdiagnosis: an underrecognized cause of confusion and harm in cancer screening. J Natl Cancer Inst. 2000;92:1280-1282. FREE FULL TEXT
35. Dammas S, Patz EF Jr, Goodman PC. Identification of small lung nodules at autopsy: implications for lung cancer screening and overdiagnosis bias. Lung Cancer. 2001;33:11-16. FULL TEXT | WEB OF SCIENCE | PUBMED
36. Lindell RM, Hartman TE, Swensen SJ, et al. Five-year lung cancer screening experience: CT appearance, growth rate, location, and histologic features of 61 lung cancers. Radiology. 2007;242:555-562. FREE FULL TEXT
37. Henschke CI, Yankelevitz DF, Naidich DP, et al. CT screening for lung cancer: suspiciousness of nodules according to size on baseline scans. Radiology. 2004;231:164-168. FREE FULL TEXT
38. Yankelevitz DF, Reeves AP, Kostis WJ, Zhao B, Henschke CI. Small pulmonary nodules: volumetrically determined growth rates based on CT evaluation. Radiology. 2000;217:251-256. FREE FULL TEXT
39. Yankelevitz DF, Kostis WJ, Henschke CI, et al. Overdiagnosis in chest radiographic screening for lung carcinoma: frequency. Cancer. 2003;97:1271-1275. FULL TEXT | WEB OF SCIENCE | PUBMED
40. Silvestri GA, Handy J, Lackland D, Corley E, Reed CE. Specialists achieve better outcomes than generalists for lung cancer surgery. Chest. 1998;114:675-680. FREE FULL TEXT
41. Bach PB, Cramer LD, Schrag D, Downey RJ, Gelfand SE, Begg CB. The influence of hospital volume on survival after resection for lung cancer. N Engl J Med. 2001;345:181-188. FREE FULL TEXT
42. Harpole DH Jr, DeCamp MM Jr, Daley J, et al. Prognostic models of thirty-day mortality and morbidity after major pulmonary resection. J Thorac Cardiovasc Surg. 1999;117:969-979. FREE FULL TEXT
43. Stéphan F, Boucheseiche S, Hollande J, et al. Pulmonary complications following lung resection: a comprehensive analysis of incidence and possible risk factors. Chest. 2000;118:1263-1270. FREE FULL TEXT
44. Pinsky PF, Marcus PM, Kramer BS, et al. Diagnostic procedures after a positive spiral computed tomography lung carcinoma screen. Cancer. 2005;103:157-163. FULL TEXT | WEB OF SCIENCE | PUBMED
45. Goldberg KB. NCI Lung Cancer Screening Trial: The Cancer Letter. Washington, DC: National Cancer Institute; 2002.
46. Lee TH, Brennan TA. Direct-to-consumer marketing of high-technology screening tests. N Engl J Med. 2002;346:529-531. FREE FULL TEXT
47. Focus on lung cancer: screening and early detection. Lungcancer.org Web site. http://www.lungcancer.org/health_care/focus_on_lc/screening/screening.htm. Accessibility verified January 31, 2007.
48. Medicare Lung Cancer Screening Benefit Act of 2006, HR 5514. http://thomas.loc.gov. Accessibility verified January 31, 2007.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter     What's this?

RELATED LETTERS

Computed Tomography Screening for Lung Cancer
Ambarish Gopal and Matthew J. Budoff
JAMA. 2007;298(5):513.
EXTRACT | FULL TEXT  

Computed Tomography Screening for Lung Cancer
Christine D. Berg and Denise R. Aberle
JAMA. 2007;298(5):513-514.
EXTRACT | FULL TEXT  

Computed Tomography Screening for Lung Cancer
Lorenzo Spaggiari, Giulia Veronesi, Massimo Bellomi, and Patrick Maisonneuve
JAMA. 2007;298(5):514.
EXTRACT | FULL TEXT  

Computed Tomography Screening for Lung Cancer
Claudia I. Henschke, David Yankelevitz, James P. Smith, and Olli S. Miettinen
JAMA. 2007;298(5):514-515.
EXTRACT | FULL TEXT  

Computed Tomography Screening for Lung Cancer—Reply
Peter B. Bach, James R. Jett, Ugo Pastorino, Melvyn S. Tockman, Stephen J. Swensen, and Colin B. Begg
JAMA. 2007;298(5):515-516.
EXTRACT | FULL TEXT  

RELATED ARTICLES

Lung Cancer
John L. Zeller, Cassio Lynm, and Richard M. Glass
JAMA. 2007;297(9):1022.
EXTRACT | FULL TEXT  

CT Screening for Lung Cancer: Spiraling Into Confusion?
William C. Black and John A. Baron
JAMA. 2007;297(9):995-997.
EXTRACT | FULL TEXT  


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

The Prevalence of Clinically Relevant Incidental Findings on Chest Computed Tomographic Angiograms Ordered to Diagnose Pulmonary Embolism
Hall et al.
Arch Intern Med 2009;169:1961-1965.
ABSTRACT | FULL TEXT  

Pattern of Antioxidant and DNA Repair Gene Expression in Normal Airway Epithelium Associated with Lung Cancer Diagnosis
Blomquist et al.
Cancer Res. 2009;69:8629-8635.
ABSTRACT | FULL TEXT  

Rethinking Screening for Breast Cancer and Prostate Cancer
Esserman et al.
JAMA 2009;302:1685-1692.
ABSTRACT | FULL TEXT  

The dilemma of incidental findings on cardiac computed tomography.
Hlatky and Iribarren
J Am Coll Cardiol 2009;54:1542-1543.
FULL TEXT  

Informed participation in a randomised controlled trial of computed tomography screening for lung cancer
van den Bergh et al.
Eur Respir J 2009;34:711-720.
ABSTRACT | FULL TEXT  

Are We Coming Full Circle for Lung Cancer Screening a Second Time?
Bepler
Am. J. Respir. Crit. Care Med. 2009;180:384-385.
FULL TEXT  

The changing epidemiology of lung cancer with a focus on screening
Silvestri et al.
BMJ 2009;339:b3053-b3053.
FULL TEXT  

CT lung cancer screening in the UK
EDEY and HANSELL
Br. J. Radiol. 2009;82:529-531.
ABSTRACT | FULL TEXT  

A review of novel biological tools used in screening for the early detection of lung cancer
Ghosal et al.
Postgrad. Med. J. 2009;85:358-363.
ABSTRACT | FULL TEXT  

Sex differences in emphysema phenotype in smokers without airflow obstruction
Sverzellati et al.
Eur Respir J 2009;33:1320-1328.
ABSTRACT | FULL TEXT  

The fruits of our efforts: time for a different view of lung cancer and CT screening
Detterbeck
Thorax 2009;64:465-466.
FULL TEXT  

Pulmonary Nodules: Volume Repeatability at Multidetector CT Lung Cancer Screening
Marchiano et al.
Radiology 2009;251:919-925.
ABSTRACT | FULL TEXT  

REVIEW PAPER: The Role of Inflammation in Mouse Pulmonary Neoplasia
Bauer and Rondini
Vet Pathol 2009;46:369-390.
ABSTRACT | FULL TEXT  

Effect of CT screening on smoking habits at 1-year follow-up in the Danish Lung Cancer Screening Trial (DLCST)
Ashraf et al.
Thorax 2009;64:388-392.
ABSTRACT | FULL TEXT  

Stem Cells and the Natural History of Lung Cancer: Implications for Lung Cancer Screening
van Klaveren et al.
Clin. Cancer Res. 2009;15:2215-2218.
ABSTRACT | FULL TEXT  

Biomarkers for Lung Cancer Screening: Interpretation and Implications of an Early Negative Advanced Validation Study
Hirschowitz
Am. J. Respir. Crit. Care Med. 2009;179:1-2.
FULL TEXT  

Plasma DNA Quantification in Lung Cancer Computed Tomography Screening: Five-Year Results of a Prospective Study
Sozzi et al.
Am. J. Respir. Crit. Care Med. 2009;179:69-74.
ABSTRACT | FULL TEXT  

Anxiety, Fear of Cancer, and Perceived Risk of Cancer following Lung Cancer Screening
Byrne et al.
Med Decis Making 2008;28:917-925.
ABSTRACT  

The Pittsburgh Lung Screening Study (PLuSS): Outcomes within 3 Years of a First Computed Tomography Scan
Wilson et al.
Am. J. Respir. Crit. Care Med. 2008;178:956-961.
ABSTRACT | FULL TEXT  

Screening for Small-Cell Lung Cancer: A Follow-Up Study of Patients With Lambert-Eaton Myasthenic Syndrome
Titulaer et al.
JCO 2008;26:4276-4281.
ABSTRACT | FULL TEXT  

Radiotracer-Guided Thoracoscopic Resection is a Cost-Effective Technique for the Evaluation of Subcentimeter Pulmonary Nodules
Grogan et al.
Ann. Thorac. Surg. 2008;86:934-940.
ABSTRACT | FULL TEXT  

Difficulties encountered managing nodules detected during a computed tomography lung cancer screening program
Veronesi et al.
J. Thorac. Cardiovasc. Surg. 2008;136:611-617.
ABSTRACT | FULL TEXT  

Extracardiac findings: what is a cardiologist to do?
Douglas et al.
J Am Coll Cardiol Img 2008;1:682-687.
FULL TEXT  

Low-dose lung computed tomography screening before age 55: estimates of the mortality reduction required to outweigh the radiation-induced cancer risk
Berrington de Gonzalez et al.
J Med Screen 2008;15:153-158.
ABSTRACT | FULL TEXT  

Effect of dietary green tea extract and aerosolized difluoromethylornithine during lung tumor progression in A/J strain mice
Anderson et al.
Carcinogenesis 2008;29:1594-1600.
ABSTRACT | FULL TEXT  

Computed Tomography Screening for Lung Cancer in a High-Risk Population: Update on Current Status
Russo et al.
JNCI J Natl Cancer Inst 2008;100:1043-1044.
FULL TEXT  

Estimating Long-term Effectiveness of Lung Cancer Screening in the Mayo CT Screening Study
McMahon et al.
Radiology 2008;248:278-287.
ABSTRACT | FULL TEXT  

CaSm (LSm-1) Overexpression in Lung Cancer and Mesothelioma Is Required for Transformed Phenotypes
Watson et al.
Am. J. Respir. Cell Mol. Bio. 2008;38:671-678.
ABSTRACT | FULL TEXT  

Early detection of cancer: lessons from lung cancer CT screening
Paleari et al.
Thorax 2008;63:566-566.
FULL TEXT  

Tailored CT: primum non nocere
LAUTIN et al.
Br. J. Radiol. 2008;81:442-443.
ABSTRACT | FULL TEXT  

Update in Lung Cancer 2007
Dubey and Powell
Am. J. Respir. Crit. Care Med. 2008;177:941-946.
FULL TEXT  

Cancer risks from diagnostic radiology
HALL and BRENNER
Br. J. Radiol. 2008;81:362-378.
ABSTRACT | FULL TEXT  

Response to "CT screening for lung cancer: update 2007".
Bach
The Oncologist 2008;13:608-609.
FULL TEXT  

In Reply
Henschke and Yankelevitz
The Oncologist 2008;13:610-612.
FULL TEXT  

Knowing me, knowing you
Lenzer and Brownlee
BMJ 2008;336:858-860.
FULL TEXT  

Unreported Financial Disclosures
Henschke and Yankelevitz
JAMA 2008;299:1770-1770.
FULL TEXT  

Computed Tomography Screening for Lung Cancer
Bach
Clin. Cancer Res. 2008;14:2511-2511.
FULL TEXT  

Reply to the Letters to the Editor from Bach and Silvestri
Henschke
Clin. Cancer Res. 2008;14:2511-2511.
FULL TEXT  

Overdiagnosis in lung cancer: different perspectives, definitions, implications
Bach
Thorax 2008;63:298-300.
FULL TEXT  

A critical appraisal of overdiagnosis: estimates of its magnitude and implications for lung cancer screening
Reich
Thorax 2008;63:377-383.
ABSTRACT | FULL TEXT  

Commentary: Lung Cancer Screening--Progress or Peril
Mulshine
The Oncologist 2008;13:435-438.
FULL TEXT  

Commentary: CT Screening for Lung Cancer--Caveat Emptor
Jett and Midthun
The Oncologist 2008;13:439-444.
FULL TEXT  

Screening for Lung Cancer
Ravenel et al.
Am. J. Roentgenol. 2008;190:755-761.
ABSTRACT | FULL TEXT  

Long-Term Use of Supplemental Multivitamins, Vitamin C, Vitamin E, and Folate Does Not Reduce the Risk of Lung Cancer
Slatore et al.
Am. J. Respir. Crit. Care Med. 2008;177:524-530.
ABSTRACT | FULL TEXT  

Computed Tomography Screening for Lung Cancer
Wilck
Ann. Thorac. Surg. 2008;85:S699-S700.
FULL TEXT  

Chromosomal Aneusomy in Bronchial High-Grade Lesions Is Associated with Invasive Lung Cancer
Jonsson et al.
Am. J. Respir. Crit. Care Med. 2008;177:342-347.
ABSTRACT | FULL TEXT  

A Macrophage Gene Expression Signature Defines a Field Effect in the Lung Tumor Microenvironment
Stearman et al.
Cancer Res. 2008;68:34-43.
ABSTRACT | FULL TEXT  

CT Screening for Lung Cancer: Update 2007
Henschke and Yankelevitz
The Oncologist 2008;13:65-78.
ABSTRACT | FULL TEXT  

Screening programme evaluation applied to airport security
Linos et al.
BMJ 2007;335:1290-1292.
FULL TEXT  

Spiral Computed Tomography and Lung Cancer: Science, the Media, and Public Opinion
Schnoll et al.
JCO 2007;25:5695-5697.
FULL TEXT  

Panel of Serum Biomarkers for the Diagnosis of Lung Cancer
Patz et al.
JCO 2007;25:5578-5583.
ABSTRACT | FULL TEXT  

Update in Oncology
Schnipper
ANN INTERN MED 2007;147:775-782.
FULL TEXT  

Commentary: Early Diagnosis of Lung Cancer: Where Do We Stand?
Paleari et al.
The Oncologist 2007;12:1433-1436.
FULL TEXT  

Computed Tomography -- An Increasing Source of Radiation Exposure
Brenner and Hall
NEJM 2007;357:2277-2284.
FULL TEXT  

Overstating the Evidence for Lung Cancer Screening: The International Early Lung Cancer Action Program (I-ELCAP) Study
Welch et al.
Arch Intern Med 2007;167:2289-2295.
ABSTRACT | FULL TEXT  

A Midpoint Assessment of the American Cancer Society Challenge Goal to Decrease Cancer Incidence by 25% Between 1992 and 2015
Sedjo et al.
CA Cancer J Clin 2007;57:326-340.
ABSTRACT | FULL TEXT  

S-Adenosylmethionine as a Biomarker for the Early Detection of Lung Cancer
Greenberg et al.
Chest 2007;132:1247-1252.
ABSTRACT | FULL TEXT  

Low-Dose Computed Tomography Screening for Lung Cancer and Pleural Mesothelioma in an Asbestos-Exposed Population: Baseline Results of a Prospective, Nonrandomized Feasibility Trial An Alpe-Adria Thoracic Oncology Multidisciplinary Group Study (ATOM 002)
Fasola et al.
The Oncologist 2007;12:1215-1224.
ABSTRACT | FULL TEXT  

Clinical Year in Review I: Lung Cancer, Interventional Pulmonology, Pediatric Pulmonary Disease, and Pulmonary Vascular Disease
Tino
Proc Am Thorac Soc 2007;4:478-481.
FULL TEXT  

Survival of Patients with Clinical Stage I Lung Cancer Diagnosed by Computed Tomography Screening for Lung Cancer
Henschke and for the International Early Lung Cancer Action Pro
Clin. Cancer Res. 2007;13:4949-4950.
FULL TEXT  

Computed Tomography Screening for Lung Cancer
Gopal and Budoff
JAMA 2007;298:513-513.
FULL TEXT  

Computed Tomography Screening for Lung Cancer
Spaggiari et al.
JAMA 2007;298:514-514.
FULL TEXT  

Computed Tomography Screening for Lung Cancer
Berg and Aberle
JAMA 2007;298:513-514.
FULL TEXT  

Computed Tomography Screening for Lung Cancer
Henschke et al.
JAMA 2007;298:514-515.
FULL TEXT  

CT screening for lung cancer not shown to reduce mortality
Hodgson
Thorax 2007;62:607-607.
FULL TEXT  

CT Screening for Lung Cancer: Spiraling Into Confusion?
Black and Baron
JAMA 2007;297:995-997.
FULL TEXT  

Continuing Uncertainty About CT Screening for Lung Cancer
JWatch General 2007;2007:1-1.
FULL TEXT  





HOME | CURRENT ISSUE | PAST ISSUES | TOPIC COLLECTIONS | CME | SUBMIT | SUBSCRIBE | HELP
CONDITIONS OF USE | PRIVACY POLICY | CONTACT US | SITE MAP
 
© 2007 American Medical Association. All Rights Reserved.