Quit smoking years ago? You may still need lung cancer screening

Quitting smoking is one of the best things you can do for your health. It lowers your risk of lung cancer and many other serious health conditions.

But even if you quit smoking years ago, do you still need lung cancer screening? For some people, the answer is yes.

We asked two lung specialists what former smokers should know about their lung cancer risk and why annual screening may still be recommended.

Why your lung cancer risk can remain after quitting smoking

Quitting smoking lowers your risk of lung cancer. But that risk doesn't disappear immediately. 

Smoking can damage your lungs over time, and people who smoked heavily for many years may continue to have a higher risk of lung cancer compared to people who have never smoked

Your risk depends on several factors, including: 

• How much you smoked
• How long you smoked
• Your age 
• How many years it's been since you quit.

Other factors, such as a family history of lung cancer, exposure to radon or asbestos, and certain lung conditions (like COPD or emphysema), can also affect your risk.

Smoking is the leading risk factor for lung cancer — but it isn't the only one. People who have never smoked can develop lung cancer, too. 

Routine lung cancer screening recommendations, however, are primarily based on age and smoking history.

“It’s a common myth that once you quit smoking, you no longer need to worry about lung cancer screening,” explains Dr. Brett Grizzell, a cardiothoracic surgeon at Ascension Via Christi. “Stopping smoking makes a big difference in lowering your risk, but it doesn't erase your smoking history. Some people may still qualify for screening years after their last cigarette.”

What is lung cancer screening?

Lung cancer screening is a noninvasive test that checks for signs of lung cancer before symptoms appear. Lung screenings are recommended for certain people with a history of smoking who have a higher risk of developing lung cancer.

The screening uses a low-dose computed tomography (CT) scan, which takes detailed images of your lungs using a small amount of radiation. 

“A low-dose CT scan is a quick, painless test,” says Dr. Abdel-ghanieAbu-Samra, a pulmonologist at Ascension Via Christi. “The scan itself uses around 75% less radiation compared to a typical CT scan and takes just a few minutes.”

While screening can't prevent lung cancer, it can help detect the disease early — often before symptoms develop — when treatment may be more effective. For people who qualify, screening is generally recommended once a year.

Am I eligible for lung cancer screening?

While lung cancer screening recommendations can vary, you may be a good candidate for annual screening if you:

• Are between ages 50 and 80 
• Currently smoke or have smoked within the past 15 years
• Have a 20 pack-year smoking history

If you fall into all three of these categories, you may be eligible for a low-dose CT scan.

What is a pack-year?

A pack-year is a way to measure how much you’ve smoked over time. To calculate pack-years, multiply the number of packs of cigarettes you smoked each day by the number of years you smoked, says Dr. Grizzell.

For example:

• One pack per day for 20 years = 20 pack-years
• Two packs per day for 10 years = 20 pack-years
• Half a pack per day for 40 years = 20 pack-years

If your smoking habits changed over the years or you’re not sure how to calculate your smoking history, your doctor can help you estimate your total pack-years.

What happens during a lung cancer screening

During the screening, you'll lie on a table that moves through a CT scanner while it takes detailed images of your lungs. The scan is painless, doesn't require an incision and usually takes only a few minutes.

Screening is intended for people who don't have symptoms of lung cancer.

What if I have symptoms of lung cancer?

Signs of lung cancer can be subtle, but possible symptoms include:

• A persistent cough that doesn’t go away or keeps returning
• Coughing up blood
• Chest pain 
• Hoarseness
• Recurring lung or chest infections
• Shortness of breath
• Unexplained weight loss

If you’re experiencing any of these symptoms, contact your doctor. You may need diagnostic testing rather than a routine lung cancer screening.

What happens after a lung cancer screening

After your lung scan, your healthcare provider will review the results and explain the findings and any recommended next steps.

“Depending on what the scan shows, your doctor may recommend that you continue with annual screening or have additional imaging or tests to take a closer look at something that was found,” says Dr. Grizzell.

Keep in mind that a finding that needs follow-up doesn't necessarily mean you have lung cancer, he adds. 

Lung screening benefits and limitations

The main benefit of lung cancer screening is that it may detect lung cancer earlier, which increases the chances of successful treatment.

However, screening has limitations. A low-dose scan can’t prevent lung cancer or guarantee that every cancer will be found.

“Sometimes, a scan detects something that looks concerning but turns out not to be cancer,” says Dr. Abu-Samra. “This is called a false-positive result, and your doctor may want to do additional imaging or tests to be sure.”

When should former smokers stop lung cancer screening?

Annual lung cancer screening generally stops when a person:

• Turns 81 years old
• Has not smoked for 15 years
• Develops a health condition that makes them unable or unwilling to undergo treatment if lung cancer is found

Your healthcare provider can help determine whether continued screening is appropriate based on your age, smoking history and overall health.

Do I need lung cancer screening if I quit more than 15 years ago?

If you quit smoking more than 15 years ago, you may no longer meet the time-since-quitting screening recommendations. However, the number of years since you quit is only one part of understanding your lung cancer risk.

“The 15-year mark doesn't mean your lung cancer risk suddenly goes away,” notes Dr. Grizzell. “It's part of one set of screening recommendations, but your overall smoking history and other risk factors still matter. If you quit more than 15 years ago, it's still worth having a conversation with your doctor about your individual risk and whether screening is recommended.”

How to find out if lung cancer screening is right for you

If you've smoked in the past, start by talking with your primary care doctor or healthcare provider.

Before your appointment, Dr. Abu-Samra says it can help to gather a few details:

• Your smoking history: About how many packs you smoked each day and for how many years
• When you quit: The year you stopped smoking
• Your health history: Any lung conditions, family history of lung cancer or other possible risk factors
• Your questions: Whether you qualify for screening, what the scan involves and what happens if something is found

You can also ask about insurance coverage and any out-of-pocket costs. Depending on your insurance plan and whether you meet its coverage requirements, lung cancer screening may be covered at no cost to you. Just make sure to check with your insurance plan before scheduling to confirm your coverage. If you don't have insurance, talk with your healthcare provider about screening options and resources that may be available to you.

Talk with your doctor about lung cancer screening

Even if you quit smoking years ago, lung cancer screening may still be recommended for you. Your doctor can help you understand your risk and decide whether a yearly scan makes sense for your health.

If screening is right for you, ask your care team about lung cancer screening options available through Ascension in your area.

Next steps and helpful resources

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