Metastatic lung cancer occurs when lung cancer cells break away from a tumor and travel to other parts of your body through the blood or lymph system. Lung cancer can be metastatic at the time of diagnosis or following treatment. Because symptoms do not develop when lung cancer is present, it is common for the cancer to metastasize before it is diagnosed.

Even though the cancer may have formed a tumor in a new location in the body, it is still named after the part of the body where it started. For example, if lung cancer spreads to the brain, it is called metastatic lung cancer. The most common sites of metastases for lung cancer are the other lung, adrenal gland, bones, brain and liver. If you have been treated for lung cancer and now have cancer cells in any of these areas, it is most likely that the lung cancer has spread.

Metastatic lung cancer is not the same as recurrent lung cancer. Recurrent lung cancer is cancer that returns to the same part of the same lung after treatment, rather than traveling to other parts of the body. If cancer develops in the lung that wasn’t previously affected, it is almost always a new metastasized cancer, not a recurrence. In all cases, a metastatic tumor is always caused by cancer cells migrating from another part of the body.

Metastatic lung cancer treatment options

In general, metastatic cancers are treated based on the original site of the cancer. The drugs used to treat your lung cancer may be used for metastases. The cancer cells themselves have not changed but simply are living in a new place.

Drug therapy is used to treat most cases of lung cancer that has spread to your liver. Options for brain metastases include radiation therapy, chemotherapy and/or steroids. Surgery is an option in very specific cases.

Radiation therapy or drug therapy are options for lung cancers that have spread to bone. Drugs would be used if you are not experiencing pain or there is no danger of bone breakage. Radiation therapy would be used if you have pain or your bone is fragile.

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