Asthma or COPD: How Symptoms Could Mask Signs of Lung Cancer

Certain chronic conditions that affect the lungs, such as asthma and chronic obstructive pulmonary disease (COPD), can have symptoms that mimic lung cancer. A recent study found that this could delay a timely lung cancer diagnosis. The study was published in the British Journal of Cancer.

The study focused on people already living with chronic conditions that have symptoms similar to those of lung cancer. The researchers found that people with only 1 chronic condition were diagnosed with lung cancer about a month later than people who did not have a chronic condition. People who had 2 or more chronic conditions were diagnosed more than 2 months later.

For some people, the delay in diagnosis could be explained because they had symptoms of another condition that masked the early signs of lung cancer. This can make it harder for doctors to identify when cancer has developed.

“For people with asthma or COPD, it is critically important that they talk with their doctor about monitoring and screening for potential lung cancers. The sooner a patient is diagnosed, the sooner they can start treatment. And the sooner they start treatment, the more likely they are to have a good outcome,” said Charu Aggarwal, MD, MPH, FASCO, an American Society of Clinical Oncology (ASCO) expert and the Leslye M. Heisler Professor for Lung Cancer Excellence at Penn Medicine.

How are asthma, COPD, and lung cancer symptoms different?

Asthma, COPD, and lung cancer all start in the respiratory system. They all can cause breathing problems. But how are they different?

• Asthma is a condition in which the airways become inflamed and narrowed.
• COPD is a condition caused by damage to the airways or lungs over time.
• Lung cancer starts when cells in the lungs become abnormal and grow out of control, usually forming a solid tumor. Unlike asthma and COPD, lung cancer can spread to other parts of the body.

For people with asthma, symptoms often appear during an asthma flare-up or attack. A flare-up can be triggered by things like pollen, dust, exercise, or an allergy. Flare-ups can last anywhere from a few minutes to a few days. Symptoms of asthma include wheezing and tightness in the chest.

For people with COPD, symptoms tend to get worse over time. Symptoms of COPD include coughing up mucus and having trouble breathing during physical activity.

For people with lung cancer, symptoms often don’t show up in early stages and can get worse over time, too. This makes it hard to tell the difference between COPD and lung cancer symptoms. However, lung cancer has several key signs and symptoms that are different from those of asthma or COPD, including:

• Coughing up blood or rust-colored spit
• Persistent coughing
• Chest pain that is worse when laughing, coughing, or breathing deeply
• Appetite loss
• Unexplained weight loss
• Bronchitis or pneumonia infections that keep coming back or never go away

“If you experience any new symptoms or a change in symptoms, it’s important to let your doctor know right away,” said Dr. Aggarwal. “They can help you determine the cause of any new or changing symptoms.”

Talking about lung cancer risk with your doctor

Having either asthma or COPD can increase the risk of developing lung cancer. If you have one or both conditions, talk with your doctor about your lung cancer risk. They can tell you what symptoms to watch for that may signal lung cancer. They may also recommend yearly lung cancer screening if you are eligible for it.

Some questions to ask your doctor include:

• What is my personal risk of developing lung cancer?
• What lung cancer signs should I watch for that may be different from my asthma or COPD symptoms?
• Do you recommend lung cancer screening? If so, how often?
• What can I do to help prevent lung cancer?

Dr. Aggarwal is an Associate Editor on ASCO’s Patient Information Editorial Board.