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Lung cancer is highly complex, not only to treat but also to understand. What is it, and what causes it?

Lung cancer is an uncontrolled growth of abnormal cells in one or both lungs. Here’s how it develops:

Cellular mutations

All healthy cells in the lungs – and elsewhere in the body – have a specific growth and death pattern that is designed to keep the number of cells in check at all times. Lung cancer develops when normal lung cells change, or mutate, in a way that alters their natural growth and death cycle, resulting in unregulated cell division that produces too many cells. The rapidly dividing cells do not carry out the functions of normal lung cells or develop into healthy lung tissue. Instead, they accumulate and form lung masses, or tumors, which may be visible in a chest X-ray or CT scan.

The cellular mutation that leads to the development of lung cancer is actually a series of permanent changes in the DNA sequence of a gene. In many cases, these changes occur when toxic substances, such as asbestos fibers or the chemicals in tobacco smoke, are inhaled into the lungs.

Lung cancer metastasis

As lung cancer progresses, some cancerous cells may break away from the original tumor and invade healthy tissues, such as nearby lymph nodes, or travel through the bloodstream and reach distant tissues and organs, such as the brain, adrenal glands or bones. This process is known as cancer spread, or metastasis. Any cancer that originates in the lungs and metastasizes to another tissue or organ is still classified as lung cancer, regardless of where in the body it is located.

Research continues

There is still much to be learned about how and why lung cancer develops. Through extensive research and clinical trials, the scientists and clinicians in the Thoracic Oncology Program at Moffitt Cancer Center are breaking new ground every day, and we strive to quickly incorporate our new discoveries into meaningful benefits for our patients. In recognition of our efforts, Moffitt has been named a Lung Cancer Center of Excellence by the National Cancer Institute.

If you have questions about how lung cancer develops, you are welcome to talk with a specialist at Moffitt. To request an appointment, call 1-888-663-3488 or submit a new patient registration form online. We do not require referrals.