What Is Lung Cancer?

Lung cancer is the leading cause of cancer death in both men and women. Lung cancer is a cancer that usually starts in the lining of the bronchi (the medium-sized airways within lungs), but can also begin in other areas of your respiratory system, including the trachea (main breathing tube), bronchioles (smaller branches of the air passages), or alveoli (the tissue farther out in the periphery of the lung).

Lung cancers are believed to develop over a period of many months to years. Nearly all lung cancers are "carcinomas"—tumors that begin in the lining or covering tissues of an organ. The tumor cells of each type of lung cancer grow and spread differently, and the treatments of these various types differ to some extent. About 85-90% of lung cancers belong to the group called non-small cell lung cancer.

Clinical Trials

Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you 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.

Before beginning treatment, ask your doctor about any clinical trials you should consider. Learn more about clinical trials for cancer patients.

Clinical trial eligibility flowcharts

Eligibility flowcharts map clinical trials to specific types of cancers to determine if a participant is eligible for the particular clinical trial. View all thoracic and lung cancer eligibility flowcharts at the Stanford Cancer Institute.

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