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What is lung cancer?
Lung cancer is not a single disease but rather a group of cancers that develop in the lung. Cancer occurs when cells mutate (change abnormally) and begin growing out of control. These cells form tumors that can often be seen on a chest X-ray.
Some tumors that form in the lung are benign (noncancerous), meaning they do not grow into surrounding areas or spread in the body. Malignant (cancerous) tumors grow into nearby tissues or spread to other parts of the body (metastasize).
A biopsy is required to determine the diagnosis of a tumor that appears suspicious on imaging.
How does lung cancer develop? Many patients wonder why they developed lung cancer or if they are at a high risk for the disease.
In general, cancer develops after the genetic material in cells changes abnormally and the cells begin growing out of control. When there are enough of these abnormal cells, they can form a tumor.
Lung cancer often is a result of chronic exposure to tobacco smoke, either from smoking or from being around secondhand smoke. It also is linked to exposure to certain substances like radon gas or asbestos, or from prior radiation treatment to or over the lungs.
People who have had lung cancer before are at higher risk of recurrence. People who have a close relative who has had lung cancer are are slightly higher risk of developing the disease.
The Stanford Medicine Online Second Opinion program offers you easy access to our world-class doctors. It’s all done remotely and you don’t have to visit our hospital or one of our clinics for this service. You don’t even need to leave home!
Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you may have access to the latest, advanced clinical trials.
Open trials refer to studies currently accepting participants. Closed trials are not currently enrolling, but may open in the future.