Can lung cancer occur without symptoms?
The leading cause of cancer deaths can often present without any major symptoms. Learn how lung cancer is detected and why early screening is critical.
Why lung cancer can go undetected
Lung cancer is the third most common cancer in Iowa and the leading cause of cancer death in both Iowa and the U.S.
However, many people can have lung cancer and not even know it.
"That's one of the biggest challenges with lung cancer," says Kim Baker-El Abiad, MD, clinical associate professor of internal medicine–pulmonary, critical care and occupational medicine at UI Health Care. "Things can grow in the lungs and be present in the lungs for some time before they actually cause any symptoms."
How is lung cancer detected without symptoms?
It is possible for lung cancer to develop without noticeable symptoms, especially in its early stages.
In fact, many lung cancers are asymptomatic during their initial phases. This is primarily because the lungs have few nerve endings, making it difficult to feel pain or discomfort even as tumors grow. Small tumors often do not interfere with lung function, further contributing to their silent nature.
Asymptomatic cases are often discovered incidentally during imaging tests conducted for unrelated health concerns such as chest X-rays or CT scans.
"Oftentimes, patients will come in for something else, have imaging done, and their doctor discovers a spot on their lungs that calls for further testing," Baker-El Abiad says. "It’s completely understandable that they’d be shocked by the news."
Early symptoms of lung cancer to watch for:
While lung cancer often begins without obvious signs, symptoms may start to appear as the disease progresses. Recognizing these early changes can help you seek care sooner and improve your chances of successful treatment. Below are some of the key symptoms to look out for.
- Persistent cough
A chronic cough that doesn’t go away or changes in character, such as becoming deeper or producing blood-tinged sputum, can be an early warning sign. - Shortness of breath
Many people attribute breathlessness to aging or lack of fitness, but persistent difficulty breathing can be a symptom of lung cancer. - Chest pain
Discomfort or pain in the chest that worsens with deep breathing, coughing, or laughing might indicate lung cancer. - Unexplained fatigue
Feeling unusually tired without a clear reason is a symptom that’s easy to ignore but could be linked to lung cancer. - Unexplained weight loss
Losing weight without trying is a potential red flag for various cancers, including lung cancer. - Hoarseness
A change in voice tone or hoarseness may occur if a lung tumor presses on the nerve that controls the larynx.
- Recurrent infections
Frequent bouts of pneumonia or bronchitis could signal a blockage in the airways caused by a tumor.
Why early detection for lung cancer matters
"I think it’s very hard for patients to understand how they have lung cancer without any symptoms," Baker-El Abiad says. "But cancer in the lung can be there for years before any symptoms occur."
If you fall into a high-risk category—such as being age 50 to 80 with a significant smoking history—discuss lung cancer screening with your health care provider now. Even without symptoms, regular screenings can catch the disease early, when treatment is most effective.
Knowledge and proactive care are your best defenses against this silent threat.
