The symptoms of the cancer vary depending on several factors, including where in the lung the tumor is found. If the cancer is located in one of the bronchi, it can irritate the lining of the bronchus (one of the main airways that branches off of the trachea or windpipe) and cause a chronic cough. The cancerous area may bleed when a person coughs.

If the tumor grows larger, it may gradually fill the bronchus so that air can't pass in or out. A blocked bronchus may also cause repeated lung infections or pneumonia.

A tumor located in the outer part of the lung may not produce any symptoms until it is fairly large. Sometimes the first sign may be chest pain from the tumor growing into the lining of the lungs or the ribs and muscle of the chest wall.

A person's lungs have extensive networks of blood and lymph vessels. Cancer cells may grow into these vessels and be carried by the blood or lymph to circulate through the body. The cancer cells may then be deposited in other organs of the body. A new colony of cancer cells, which started in another organ, is known as metastasis.

The first site of tumor metastasis is usually the lymph nodes within the lungs and the mediastinum (the space between the two lungs in the middle of the chest).

It is possible for cancer cells that begin in other organs to spread to the lungs. These cases are very different medical problems, however. Depending on the organ of origin, such cases might be termed "primary breast cancer, metastatic to the lungs," or "primary kidney cancer, metastatic to the lungs."

Copyright 2003 National Women's Health Resource Center Inc. (NWHRC)