Why won’t lung cancer screening take off?
By Jeff Alpert
Lung cancer remains the second most commonly diagnosed cancer among both men and women. It is also the most deadly, with nearly 150,000 people succumbing to the disease every year — enough people to fill a football stadium. Twice.
If football fans went to such a stadium in October, they would see many NFL players wearing pink mouthguards, shoelaces, and other athletic accessories to promote breast cancer awareness. Inarguably, several national organizations supporting breast cancer screening, education and research have made breast cancer awareness a branding success.
What many do not realize is that just as breast cancer has a well-established screening program and an effective imaging test (the mammogram), lung cancer does, too. Nearly a decade ago, a standardized lung cancer screening program was developed in the United States, which uses chest CT scans to detect early stage treatable lung cancers. Approved for current and former smokers between the ages of 55 and 77, lung cancer screening is covered by Medicare and many private insurers. A large nationwide trial (the National Lung Screening Trial, or NLST, published in 2011) showed that lung cancer screening with chest CT can reduce deaths from lung cancer by 20%.
The screening exam is painless, fast, and poses little risk. In contrast to a mammogram, no one flattens your lungs between two plastic paddles during a lung cancer screening exam. The chest CT can be completed in the time it takes to breathe a single breath. And with only a fraction of the radiation dose typically associated with CT imaging of the lungs, this annual low-dose CT exam is safe.
Yet of the nearly 7 million eligible patients, less than 5% — only about 250,000 — have been screened. Why so few?
Widespread acceptance of lung cancer screening faces several obstacles, most rooted in myth and miscommunication. The NLST (mentioned above) found a clear benefit to screening current and former smokers with chest CTs. Researchers in Canada (the Pan-Can trial) and Europe (the NELSON trial) reached similar conclusions. Despite this solid, carefully executed research, groups such as the American Academy of Family Physicians (AAFP) have failed to endorse lung cancer screening in high-risk patients due to a “lack of sufficient evidence.” The reason for this decision is unclear, but one thing is certain: formal support from groups like the AAFP would encourage primary care physicians to embrace lung cancer screening. Front-line health care providers serve as gatekeepers who can identify appropriate patients, discuss the potential benefits of early lung cancer detection, and order screening exams for their patients.
For many patients, getting a doctor’s order for a screening CT eliminates just one roadblock. In much of the southern and western United States, a patient may have to travel over 200 miles to reach an approved lung cancer screening center. For many older Americans, traveling such a distance may impose physical or economic hardship. For others, the required travel time may equate to lost wages. All this frustration may lead an ambivalent patient to sit down, light a cigarette, and call the whole thing off.
This brings up a nagging issue, one that may disenfranchise smokers from taking part in lung cancer screening: Medicare and many private insurers mandate that every lung cancer screening patient undergo smoking cessation counseling. This required counseling session, telling a high-risk patient to quit smoking before they undergo a (potentially positive) cancer screening test, unwittingly creates another significant obstacle to lung cancer screening: guilt.
To qualify for lung cancer screening, a person must have a 30-pack-year smoking history, which is equivalent to smoking at least 1 pack of cigarettes per day for 30 years. That means that this test is targeted at committed, or even lifelong, smokers. These people have been ensnared by the addictive properties of tobacco, and they already know that smoking significantly increases their risk of lung cancer. It’s reasonable to assume that forcing them to undergo counseling does not provide new information to a long-term smoker, but it does impart a sense of blame for a potentially positive test.
This feeling of shame may account for the lack of enthusiasm about lung cancer screening, which stands out compared to screening for breast, colon and even skin cancers. People aren’t counseled to avoid genetic predispositions, dietary choices, or sunlight before they undergo other types of screening exams. Why should we impose such a requirement for a lung cancer screening CT?
The goal of lung cancer screening with low-dose chest CT is to identify and treat early-stage lung cancers and to reduce lung cancer-related deaths. Yet the most important rate-limiting step is getting people onto the CT scanner to complete the screening test. In these older patients, who have already established long-term tobacco use, smoking cessation is not the ultimate goal. One could rightly argue that the (lung) damage is already done.
We know that lung cancer screening with low-dose chest CT works. But for this program to flourish, we shouldn’t pretend we’ll save lives by nagging lifelong smokers to quit.
Jeff Alpert, M.D. is an assistant professor of radiology at New York University School of Medicine, where he specializes in cardiothoracic imaging. During one particularly raucous summer in his early 20’s, he accrued a 0.04 pack-year smoking history.