Angela Criswell, director of quality screening and program initiatives at GO2 Foundation for Lung Cancer, discusses early detection and screening for lung cancer.
Kristie L. Kahl: Can you discuss what the risk factors for lung cancer are?
Angela Criswell: So the main risk factors for lung cancer are one’s age and smoking history. Those are the risk factors that define someone as being at high risk for lung cancer when it comes to determining eligibility for lung cancer screening, which I think we're going to talk about in just a moment.
While the majority of lung cancers are diagnosed, people who are older and who have either a current or a previous history of heavy smoking, there really is still a lot more to the story. There are other recognized risk factors including environmental exposures, such as high levels of radon in an enclosed environment, such as your home or your workplace, also, some occupational exposures like diesel fumes, heavy metals, silica dust, asbestos, and also secondhand smoke, among other things. Having a family member with a history of lung cancer can indicate one has a heightened risk of lung cancer. And then if you have a prior cancer history of your own, like head and neck cancer or lymphoma, that also may put you at increased risk.
Kristie L. Kahl: With these risk factors, who should be getting screened, or at the least who should be asking about screening?
Angela Criswell: So the current recommendation for lung cancer screening from the US Preventive Service Task Force is for individuals who are ages 50 to 80, with a current or a prior 20-pack year history of smoking. So that means if they smoked on average, one pack a day for 20 years or two packs a day over a 10-year time span, for example. And then also, if they formerly smoked and have since quit, they need to have quit within the past 15 years. That is the population for which the benefits of lung cancer screening are clear based on our current scientific evidence.
But again, though, this doesn't take into account the other risk factors that I just touched on. So in those cases, we encourage individuals to discuss their lung cancer risk with their physician or healthcare team if screening might be appropriate for them, though we don't have quite as much evidence to guide decisions about how often or how long they should be screened, and what the risks versus benefits might be for them. Also, they'll likely have some out-of-pocket costs for their screening since they don't meet those defined criteria from the US Preventive Services Task Force or from the Center for Medicare and Medicaid Services.
Kristie L. Kahl: If you're eligible for screening, what exactly does that consist of?
Angela Criswell: Screening is done by low-dose computed tomography, or low-dose CT for short. A CT machine takes 3D X-RAY pictures of your lungs using a small amount of radiation. And this radiation level is more than a chest X-RAY, but it is much lower than other types of CT scans. The CT scan itself is very quick, it takes only a few seconds to complete the scan. And it is a painless process. So it requires no needles or dyes and advanced preparation such as fasting or anything of that sort.
Kristie L. Kahl: How often should people be getting screened?
Angela Criswell: So lung cancer screening should be done every year. This is true as long as you remain at high risk for lung cancer based on your age and smoking history. And as long as you are healthy enough to consider treatment options if something concerning is detected. If you have been participating in screening due to other risk factors, then age and smoking history, say because of occupational exposure, then we don't really have evidence to say for sure how frequently or for how many years you should be screened. But the evidence is growing. So this is really something for you to discuss with your physician. There may be lung nodules detected during your screening that will lead to follow up. Most nodules are normal and are not cancer. And so they should just be watched every year to see if they grow or change. And some nodules might look a little suspicious and so you might need to come back in three months or six months for a follow up, diagnostic low-dose CT, just as the nodule has grown or changed in a way that is concerning. In some instances, your doctor might refer you for a minimally-invasive tissue sampling or biopsy or possibly surgery or other testing and treatment.
Kristie L. Kahl: What are the benefits of screening?
Angela Criswell: Studies have shown that low-dose CT lung cancer screening can find lung cancer when it is early and therefore much easier to treat and more likely to be cured. And your survival rates for lung cancer increase exponentially when it is found at an early stage versus a late stage. Early stage lung cancer can have up to a 90% chance of cure. And lung cancer screening may also show if you have some other conditions or diseases that need to be treated such as coronary artery disease, COPD, or even other cancers that may be visible on that chest scan. I also want to mention that at the same time, there are a few risks. As with all cancer screening tests, some cancers may be missed, those are called false-negatives. And lung cancer screening might find nodules that look suspicious and lead to further tests that are not actually cancerous, those are called false-positives. And as I mentioned a moment ago low dose CT does use a small amount of radiation.
Kristie L. Kahl: To bring it all together, if somebody thinks they should be getting screened, what are their next steps? Where should they go?
Angela Criswell: So if you think that lung cancer screening is right for you, you should talk to your primary care provider or another health care professional that you see regularly. They will talk with you about your risk of lung cancer and the benefits and risks of screening. And then if you want to be screened, they will refer you to a lung cancer screening program at a hospital or other facility in your community. You should be screened in an experienced center that follows approved guidelines for lung cancer screening. So, for example, Go2 foundation has designated screening Centers of Excellence nationwide. And to find a center near you, you can call our helpline at 1-800-298-2436 or visit our website and go2foundation.org.