What is Metastatic Lung Cancer?
Metastatic lung cancer is a type of cancer that affects the lungs. Unlike the cancer cells that arise from lung tissue in typical lung cancer, the cancer cells of metastatic lung cancer originate from another area of the body. Usually, another type of cancer has spread beyond its initial surroundings. These cancer cells travel through the bloodstream, or through the lymphatic system, to the lungs and invade the lung tissue. Some of the cancers which are the primary source of metastatic lung cancer include bladder, colon, prostate, breast and kidney.
Symptoms and Diagnostic Tests
The symptoms of metastatic lung cancer are similar to cancers that originate in the lungs. As the cancer cells begin to accumulate and overtake sections of lung tissue, breathing becomes more and more difficult. Shortness of breath is a common symptom associated with metastatic lung cancer. Another sign that there is cancer in the lungs is the presence of blood in the sputum (mucous that is coughed up). Chest pain and frequent coughs may indicate a problem with lung function.
There are several complications associated with this type of cancer. Fluid accumulation around the heart or between the lung and chest wall is one complication. The cancer can spread from the lungs to other areas.
Usually, there are no signs in the early stages of the cancer. Routine chest x-rays and CT scans discover the presence of a tumor in the lungs. To determine the nature of the tumor, a lung needle biopsy or surgical lung biopsy may be performed. The pleural fluid, which is the fluid between the lining of the lungs, and sputum can be tested for cancer cells.
The treatment options for this type of lung cancer depends on the extent to which the primary cancer has spread. Usually, the cancer travels freely through the bloodstream at this point and simply removing the tumor from the lung may not be effective. The cancer may recur if the primary cancer isn't treated. Chemotherapy is usually used to treat cancer that has spread to the lungs. Radiation therapy is another option.
There are several side effects associated with chemotherapy including fatigue, weight loss, hair loss, nausea and vomiting. Radiation therapy also has its drawbacks, including fatigue and lack of energy. Radiation therapy also reduces the number of white blood cells, which can leave the body susceptible to infections.
Long Term Outlook
Since the cancer in the lungs originated from another advanced stage cancer in another part of the body, the long term outlook isn't that great. It is rare for an individual with metastatic lung cancer to live longer than five years after their diagnosis. The prognosis depends on the primary cancer. Lymphoma and testicular cancer are two cancers that can be effectively treated with chemotherapy, even after they have spread to the lungs.
1. "Metastatic Cancer to the Lungs." MedlinePlus. https://www.nlm.nih.gov/medlineplus/ency/article/000097.htm
2. "Lung Cancer." MedicineNet. https://www.medicinenet.com/lung_cancer/article.htm