Our research team recently embarked on a project to understand how family physicians perceived and utilized low-dose CT (LDCT) screening for lung cancer after the release of a controversial screening recommendation from the U.S. Preventive Services Task Force (USPSTF).(www.uspreventiveservicestaskforce.org)
Scott Strayer, M.D., M.P.H.
In December 2013, the USPSTF issued a "B" recommendation(www.uspreventiveservicestaskforce.org) for LDCT screening for lung cancer in adults aged 55-80 years who have a 30 pack-year smoking history and who currently smoke or have quit within the past 15 years. Our project surveyed a convenience sample of members of the South Carolina AFP to determine family physicians' knowledge of the recommendation, assess their attitudes about screening and explore early referral patterns.
Our study results, published in the Aug. 1 issue of Cancer,(onlinelibrary.wiley.com) found that many family physicians were not aware of recommendations on this topic issued by professional organizations and agencies (including the AAFP), expressed concerns about the risk for unnecessary followup testing, and had made few patient referrals.
Although a good deal of media coverage of the study cast our findings as primarily showing a lack of knowledge by physicians, focusing only on that aspect ignores many complex factors that likely explain the survey results, including inconsistent screening recommendations across organizations, institutional barriers to implementing screening and uncertainty about the value of screening outside the clinical trial setting.
In 2011, the largest, most expensive clinical trial(www.nejm.org) ever conducted by the National Cancer Institute reported its findings in the New England Journal of Medicine: An annual LDCT scan performed on high-risk individuals reduced the risk of lung cancer death by as much as 20 percent and the risk of all-cause mortality by almost 7 percent. Chest radiographs, by comparison, did not show a reduction in lung cancer mortality.
Jan Eberth, Ph.D., M.S.P.H
Yet along with these clear benefits, the authors of the study indicated that among patients with a positive LDCT result, more than 95 percent were actually false-positive. However, less than 2 percent of patients with false-positive results underwent an invasive biopsy or surgical procedure.(jamanetwork.com) As is often the case when a new screening modality is introduced, cautious optimism and some skepticism are expected among patients and the medical community.
Many professional societies and nonprofit organizations welcomed the USPSTF's positive message in 2013 that LDCT screening for lung cancer saves lives. The number of people needing to be screened (NNS) to save one person from a lung cancer-related death (320 based on trial data)(www.cancer.gov) is comparable to that for breast cancer screening with mammography biennially in women ages 60-69 (NNS=303)(www.ajronline.org) and substantially lower than widely accepted screening for colorectal cancer with fecal occult blood testing (NNS=1,176).(www.cochrane.org)
However, the risk of invasive followup procedures for people who will not go on to be diagnosed with lung cancer is troublesome for some patients and family physicians. Concerns have also been raised about whether the benefits observed in the clinical trial setting can be replicated in communities. Further doubts were raised when the AAFP diverged from the USPSTF, issuing a recommendation statement that said the evidence is insufficient to recommend for or against LDCT screening.
Still, in early 2015, CMS stated that Medicare would cover LDCT screening(www.cms.gov) for lung cancer for asymptomatic, high-risk individuals (i.e., those ages 55-77 with a 30 or more pack-year smoking history and who currently smoke or quit less than 15 years ago) as long as a shared decision-making visit is documented before screening and all related data are entered into a CMS-approved registry for future research.
Although our study results found that many family physicians were not aware of the various organizational guidelines on this topic, expressed concerns about potentially harmful followup procedures and had made few patient referrals, about 75 percent agreed that the benefits of screening outweighed the risks, and more than 60 percent reported having five or more patients ask if they could be screened in the past year. Similar findings have been reported by investigators in other U.S. states including California,(www.jto.org) North Carolina,(www.ncbi.nlm.nih.gov) Texas,(www.ncbi.nlm.nih.gov) and New Mexico.(www.ncbi.nlm.nih.gov)
The medical community has long acknowledged the barriers to clinical guideline and national recommendation adherence and uptake by physicians,(jamanetwork.com) which include lack of familiarity with such guidelines and recommendations or their specific components, inconsistency in guidance offered by various organizations, uncertainty about the value of screening, external barriers such as lack of reimbursement, perceived lack of self-efficacy to counsel patients and inertia associated with previous practice. Even in some scenarios when a particular procedure is not recommended, physicians often prioritize their own clinical impressions in their decision-making.(www.ncbi.nlm.nih.gov)
As family physicians, we have a large volume and breadth of information to keep abreast of, and recommendations for screening and preventive services are numerous. Even for uncontroversial recommendations such as smoking cessation, primary care physicians have difficulty implementing counseling and treatment discussions(www.ncbi.nlm.nih.gov) with all eligible patients because of the frequently cited barriers(www.ncbi.nlm.nih.gov) of limited time, low physician confidence in counseling smokers and incomplete knowledge of smoking cessation guidelines.
With three-quarters of our respondents agreeing that the benefits of screening outweigh the risks and most respondents reporting that they discuss these risks and benefits with their patients, the low adoption of lung cancer screening is likely driven by factors other than a lack of knowledge. These factors may include patients' ineligibility for screening, lack of awareness or availability of local screening clinics, and little or no clinical decision support or systems-based guideline implementation assistance.
In light of some of these challenges, our research group and others have developed and tested shared decision-making tools(effectivehealthcare.ahrq.gov) to assist patients and their physicians with this challenging screening decision. Additionally, technical assistance to enable electronic health record systems to capture eligibility information and alert physicians accordingly, as well as to manage billing and documentation requirements, appears necessary.
With at least 70 percent of smokers in the United States visiting their physician annually, primary care physicians play a vital role in determining when and how at-risk individuals follow cancer screening recommendations. In the case of LDCT screening for lung cancer, the best-case scenario is that physicians know both the risks and benefits of screening (rather than the intricacies of each organization's stated guideline or recommendation) and can present an unbiased viewpoint of those elements while counseling patients to achieve true shared decision-making. Family physicians are ideally suited to address these challenges and to ensure appropriate implementation of lung cancer screening guidance.
Scott Strayer, M.D., M.P.H., is professor in the Department of Family and Preventive Medicine at the University of South Carolina School of Medicine in Columbia. He is president of the American Association for Primary Care Endoscopy.
Jan Eberth, Ph.D., M.S.P.H., is assistant professor of epidemiology and deputy director of the South Carolina Rural Health Research Center at the University of South Carolina Arnold School of Public Health.