December 21, 2023

What’s My Risk of Lung Cancer After I Quit Smoking?

Your risk goes down once you quit, but you may still need a lung cancer screening

older male patient speaking with doctor holding tablet in office

You did it, you kicked the habit! (Congratulations, by the way, that’s huge, and you should be so proud!) But now, you may be wondering: Has your risk of lung cancer gone up in smoke, too?


Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

When you quit smoking, your risk of lung cancer goes down, along with your risk for a variety of other conditions. But you’re still at a higher risk than someone who never smoked.

Pulmonologist Peter Mazzone, MD, MPH, director of Cleveland Clinic’s Lung Cancer Screening Program, explains the risk of lung cancer after you’ve quit smoking and how to determine whether you should have a lung cancer screening.

Can I still get lung cancer after quitting smoking?

Yes, you can still get lung cancer after you’ve quit smoking

“By quitting, you cut your risk of developing lung cancer quite a bit,” Dr. Mazzone says, “but there’s strong evidence to show that your risk will never get to the point of somebody who didn’t smoke.”

Your total smoking amount is calculated in “pack years,” or the number of packs you smoked per day multiplied by the number of years that you smoked. For example, all of the following examples equate to 20 pack years:

  • Half a pack of cigarettes a day for 40 years.
  • One pack of cigarettes a day for 20 years.
  • Two packs of cigarettes a day for 10 years.

Of course, life is rarely that straightforward, which means that pack years can sometimes be difficult to calculate. Maybe you quit smoking for long stretches of time, or you ramped up (or down) your number of daily cigarettes throughout the years.

There are still questions you can ask yourself to help you (and your healthcare provider) figure out your overall risk of lung cancer.

Lung cancer screening recommendations

“The younger you are when you start smoking, the heavier and the longer someone smokes, the greater their risk is of getting lung cancer,” Dr. Mazzone explains, “so the sooner a person is able to quit, the better off they are — and the lower their risk will be.”

If you’re concerned about your risk for lung cancer, schedule a conversation with a healthcare provider. They’ll ask you questions like:

  • How old were you when you started smoking?
  • How much and how often did you smoke, on average?
  • How long did you smoke? Were there periods when you quit and then started again?
  • How long has it been since you smoked?

“The answers to all of these questions contribute to your risk,” Dr. Mazzone says.

Who should be screened for lung cancer?

Lung cancer screening is recommended if you meet all three of the following criteria:

  • You are 50 to 80 years old.
  • You smoked for the equivalent of 20 or more pack years.
  • You smoked within the past 15 years.

But many people who should be screened for lung cancer just aren’t having it done.

“Lung cancer screenings have been standard of care for that eligible group of people for many years now,” Dr. Mazzone says. “Yet, the uptake of lung cancer screening is still relatively low.”

Some studies indicate that only 10% to 20% of people who are eligible for lung cancer screening actually have it done.

“I encourage anyone who is eligible to get screened,” Dr. Mazzone urges. “Let's make sure you don’t have a cancer that could be identified now instead of waiting until it has progressed.”

What if you have symptoms?

There are times when you don’t need to meet all three lung cancer screening criteria to be eligible for a screening. Tell your healthcare provider right away if you experience concerning symptoms like:

  • A new, persistent cough.
  • Coughing up blood.
  • Unexplained shortness of breath or chest pain.
  • Unintentional weight loss.

“In these cases, you may need testing to confirm or rule out the presence of lung cancer,” Dr. Mazzone notes.

If your healthcare provider recommends you be screened for lung cancer, look for a program with experts who are experienced in lung cancer evaluation and treatment and take the time to discuss its risks and benefits with you


“Enroll in a high-quality program that will take good care of you,” he stresses.

Not everyone who used to smoke needs a screening

Why isn’t lung cancer screening recommended for everyone who used to smoke? Dr. Mazonne explains that for people with a low risk of lung cancer, even those who once smoked, the risks may outweigh the benefits.

Potential risks and downsides of the screening include exposure to small amounts of radiation and the possibility of identifying benign (noncancerous) nodules in the lungs, which can cause needless anxiety.

“We always want to be sure that there is a balance that favors benefit from screening over harm,” Dr. Mazzone says. “If you have almost no chance of getting lung cancer, then the harms outweigh the benefits. You also have to be healthy enough to tolerate the evaluation and treatment of any lung nodules or lung cancers that are found during screening.”

How can I prevent lung cancer after quitting smoking?

There’s no surefire way to keep lung cancer at bay, Dr. Mazzone says, but in general, maintaining a healthy lifestyle is thought to be one of the best ways to lower your risk of developing it (along with many other conditions and diseases).

“We always encourage people to be active, to eat a healthy diet, to avoid overusing alcohol and so on,” he continues. “We believe that leading a good, healthy lifestyle likely impacts either people’s risk of developing lung cancer or their ability to have a better outcome if they do develop lung cancer.”

And remember: By quitting smoking, you’ve already taken one of the biggest steps toward staying healthy for the long term.

“Your risk of developing lung cancer goes down the further you are from having smoked.”Dr. Mazzone encourages. Every day that you live smoke-free takes you one step farther from your risk of lung cancer.

Related Articles

person on couch wincing, holding hands over abdomen
March 4, 2024
Colon Cancer in Young Adults: An Alarming Trend

A steady increase in cases in those younger than 50 started decades ago

Physician examines oversized colon with giant magnifying glass, with report in foreground
March 1, 2024
Colon Cancer Screenings: When To Start

If you’re at average risk, it’s recommended that you get your first colonoscopy at age 45

person scratching at their itchy skin on their chest
January 2, 2024
Is Itchy Skin a Sign of Cancer?

Anything from minor irritations and chronic diseases to, yes, cancer can cause persistent itching

Examining lungs
October 30, 2023
Lung Cancer Screening: What You Need To Know

Early detection of the disease can extend your life, but there are specific testing guidelines

Physican listening to patient's lungs via stethescope.
April 12, 2023
Do People With Early Lung Cancer Have Symptoms?

Knowing the signs (like a cough that won’t quit) may help some people detect lung cancer early

A person sitting in a dentist office getting a dental cleaning
April 11, 2022
Can Your Dentist Screen for Oral Cancer?

The importance of seeing your dentist twice a year

man having blood pressure checked in doctor's office
January 20, 2021
What You Need to Know About Health Screening Tests

Why you need them and which ones you need

processed sandwich meat
December 29, 2020
Can I Get Cancer From Eating Red Meat?

The link between cancer and eating red and processed meat

Trending Topics

White bowls full of pumpkin seeds, dark chocolate and various kinds of nuts
25 Magnesium-Rich Foods You Should Be Eating

A healthy diet can easily meet your body’s important demands for magnesium

Woman feeling for heart rate in neck on run outside, smartwatch and earbuds
Heart Rate Zones Explained

A super high heart rate means you’re burning more than fat

Spoonful of farro salad with tomato
What To Eat If You’ve Been Diagnosed With Prediabetes

Type 2 diabetes isn’t inevitable with these dietary changes