As reported online in CA: A Cancer Journal for Clinicians,1 based on results from the National Lung Screening Trial (NLST) sponsored by the National Cancer Institute (NCI), the American Cancer Society (ACS) has released lung cancer screening guidelines recommending that select clinicians should initiate informed discussions about screening with age-appropriate patients who have a minimum 30-pack-year smoking history and who still smoke or have quit within the past 15 years.
Significant Results
On November 4, 2010, NCI announced that ongoing NLST data demonstrated a 20% reduction in lung cancer mortality in a high-risk group randomized to 3 consecutive years of low-dose computed tomography (CT) screening examinations, compared with an equivalent group receiving chest x-rays. Equally important, NLST’s Data Safety and Monitoring Board found “no evidence of unforeseen screening effects that warranted acting contrary to the trial’s prespecified monitoring plan.”
On June 30, 2011, the NLST published its results, providing first-ever evidence from a prospective randomized controlled trial that low-dose CT screening in high-risk populations reduced lung cancer mortality.
Systematic Review
Following the NLST results, the American Cancer Society joined with the American College of Chest Surgeons, ASCO, and the National Comprehensive Cancer Network to produce a systematic review of the evidence gleaned from literature published from January 1996 through April 2012. Randomized controlled trials and observational studies were included in the study.
The joint group force looked at four key areas: potential benefits, potential harms, which populations are likely to benefit, and what screening setting is likely to be effective. In developing the guidelines, the ACS group gave findings from the NLST particular weight based on its superior size. Moreover, the majority of the NLST study sites were NCI-designated cancer centers and large academic medical centers that established quality parameters for the study.
Recommendations
After completing the review process, the subsequent guideline recommended that clinicians with access to high-volume, high-quality screening centers should initiate a discussion about screening with outwardly healthy patients, aged 55 to 74 years, who have a minimum 30-pack-year smoking history and currently smoke, or have quit within the past 15 years.
Principal elements of the clinician-patient discussion should include the following:
Benefit: Low-dose CT has been shown to effectively reduce lung cancer mortality.
Limitations: Low-dose CT does not detect all lung cancers and does not guarantee early cancer detection; not all patients who have lung cancer identified by Low-dose CT will avoid death.
Harms: Low-dose CT confers a significant percentage of false-positive results, which will require additional testing and, in some cases, an invasive procedure to determine whether an abnormality that is picked up is lung cancer or some other incidental noncancer finding. It is rare that patients with a false-positive experience have major complications from subsequent diagnostic workup.
Eligible patients should make the screening decision together with their clinicians; together they can clarify the personal values needed in effective decision-making. Patients must be willing to weigh the reduced risk of dying that screening offers with the risks and costs associated with a low-dose CT. Clinicians should not discuss low-dose CT with patients who do not meet those criteria. Further, since few payers cover the initial low-dose CT, clinicians who offer screening must help patients determine how they will ultimately pay for the test.
Conclusions
The National Lung Screening Trial has demonstrated that there is an opportunity to reduce deaths from lung cancer in high-risk groups of current and former smokers. Clinicians now face the challenge of integrating risk-assessment into their discussions with patients.
To that end, it is incumbent on cancer control organizations to devote resources toward preparing clinicians in identifying patients who are eligible for low-dose CT. Whether community-based lung cancer screening with low-dose CT will achieve the benefits observed in the NLST awaits further research. ■
Disclosure: Among the authors of the screening guidelines, Dr. Christopher R. Flowers has received consulting fees from Celgene Corporation; Spectrum; Seattle Genetics, Inc; OptumRx; Clinical Care Options; and Education Concepts Group. He has performed contracted research for Millennium Pharmaceuticals, Celgene Corporation, Spectrum, Gilead Pharmaceuticals, and Janssen Pharmaceuticals. Dr. G. Scott Gazelle is a consultant to GE Healthcare. Dr. Douglas K. Kelsey is employed by Eli Lilly and Company. Other authors reported no potential conflicts of interest.
Reference
1. Wender R, Fontham ETH, Barrera E Jr, et al: American Cancer Society lung cancer screening guidelines. CA Cancer J Clin. January 11, 2013 (early release online).
