Chronic obstructive pulmonary disease (COPD) is a group of conditions that affects the lungs. COPD and lung cancer are caused by cigarette smoking and are often comorbidities — two conditions that frequently appear in the same person at the same time. COPD increases a person’s chances of developing lung cancer. About 1 percent of people with COPD develop lung cancer each year. Up to 80 percent of people with lung cancer may have COPD.

What Is COPD?

Chronic obstructive pulmonary disease consists of several different conditions. The two most common types of COPD are emphysema and chronic bronchitis. Emphysema is damage or destruction of the alveoli (air sacs within the lungs). Chronic bronchitis is irritation and swelling of the bronchial tubes (large tubes that let air in and out of the lungs).

Emphysema and chronic bronchitis often occur at the same time. They both lead to airflow obstruction — the blockage of air from getting to the lungs. Symptoms of COPD include breathing problems, chest tightness, coughing up sputum (mucus), tiredness, and swelling in the feet or legs.

COPD is most often caused by smoking. Air pollution, infections, and genetic conditions can also cause COPD. Usually, this condition gets worse over time. People with COPD may have trouble walking, going up stairs, working, or leaving the house. COPD is one of the leading causes of death worldwide.

How COPD Affects Lung Cancer Risk

People with COPD are up to five times more likely to receive a lung cancer diagnosis than people with normal lung function. COPD most often causes squamous cell carcinoma, a subtype of non-small cell lung cancer (NSCLC).

One reason for the link between COPD and lung cancer is that these two conditions share some of the same risk factors. Cigarette smoking can cause both of these lung diseases or make them worse. This is because carcinogens (cancer-causing molecules) in cigarette smoke damage DNA and kill cells.

Cigarette smoke is not the only link between these two conditions. Even nonsmokers with COPD have a higher risk of developing lung cancer. Researchers believe that there are a few reasons why COPD and lung cancer often occur together:

• Cellular and DNA damage — COPD damages cells in the lungs, making them more likely to turn cancerous.
• Genetic susceptibility — Some people have gene changes that make them more likely to develop both COPD and lung cancer.
• Inflammation — One impact of COPD is chronic inflammation in the lungs and airways, which can lead to cancer.
• Enzymes — During COPD, the body makes enzymes that encourage cells to grow faster and become cancerous.

Some people living with COPD have a further increased risk of developing lung cancer. Older age (60 years old or older), lower body mass index, and a longer smoking history are factors that raise lung cancer risk in people with COPD.

COPD and Lung Cancer Prognosis

COPD may worsen a person’s lung cancer prognosis (outlook). In some studies, people were more likely to die from lung cancer if they also had COPD. These studies found that people with COPD were more likely to have high-grade (faster-growing) tumors, and their cancer was more likely to relapse (come back after being treated). People with COPD may have greater difficulty in tolerating cancer treatments. In other studies, people with and without COPD had similar outcomes from lung cancer.

Other factors such as genetics or lung cancer stage may play a role in a person’s outlook. The type of lung cancer may also affect survival rates. One study found that people with COPD had worse outcomes if they had squamous cell carcinoma. However, people with other types of lung cancer had a similar prognosis. More research needs to be done to better understand how COPD is linked to lung cancer outcomes.

Can You Prevent Lung Cancer?

It’s not possible to prevent lung cancer. However, you can reduce your risk of lung cancer by eliminating certain risk factors and having regular visits with your health care team.

Reducing Other Risk Factors

Several factors besides COPD affect your risk of lung cancer. You can’t change some risk factors, such as your age or your genes. However, you have control over factors. For example, smoking is a major cause of COPD and lung cancer. Quitting smoking and avoiding other people’s cigarette smoke can lower your risk.

To reduce your lung cancer risk, eliminating other risk factors may help:

• Avoid exposure to radon, a radioactive gas, by testing your home for radon levels and fixing any leaks.
• Stay away from asbestos, a material found in older buildings, mines, mills, and shipyards.
• Take precautions to limit exposure to other toxic chemicals at work, including radioactive materials, arsenic, silica, nickel compounds, and diesel exhaust.

Eating fruits and vegetables may also help protect against lung cancer. However, supplements aren’t a substitute for a balanced diet. Some studies have found that taking vitamins such as beta-carotene can increase the cancer risk for people who smoke. It’s healthier to get a variety of nutrients directly from your food.

Regular Doctor’s Visits

Imaging tests such as computed tomography (CT) scans can help catch lung cancer early. Guidelines recommend annual screening low-dose CT scans for people between the ages of 55 and 70 if they smoke. Studies have found that lung cancer screening helped improve early detection, which often led to a better prognosis.

If you are worried about lung cancer risk, talk to your doctor. They can help you understand your risk level based on your personal and family history and may be able to recommend other strategies for managing risk.

Talk With Others Who Understand

MyLungCancerTeam is the social network for people with lung cancer and their loved ones. On MyLungCancerTeam, more than 2,000 members come together to ask questions, give advice, and share their stories with others who understand life with lung cancer.

Are you living with COPD and lung cancer? Share your experience in the comments below, or start a conversation by posting on your Activities page.

References

1. Early Detection of COPD Is Important for Lung Cancer Surveillance — European Respiratory Journal
2. Understanding the Links Between Lung Cancer, COPD, and Emphysema: A Key to More Effective Treatment and Screening — Cancer Network
3. COPD — Mayo Clinic
4. Basics About COPD — Centers for Disease Control and Prevention
5. The Relationship Between COPD and Lung Cancer — Lung Cancer
6. Mechanistic Links Between COPD and Lung Cancer — Nature Reviews Cancer
7. Lung Cancer in Patients With Chronic Obstructive Pulmonary Disease. Development and Validation of the COPD Lung Cancer Screening Score — American Journal of Respiratory and Critical Care Medicine
8. Impact of Coexistent Chronic Obstructive Pulmonary Disease on the Survival of Patients With Small Cell Lung Cancer Receiving Chemotherapy — Thoracic Cancer
9. Is There An Impact on Lung Cancer Survival Due to COPD? — The American Journal of Managed Care
10. Can Lung Cancer Be Prevented? — American Cancer Society
11. Quitting Smoking for Older Adults — National Institute on Aging
12. Lung Cancer Risk Factors — American Cancer Society