Lung cancer is a complex medical condition, which is the result of cells within the lungs developing the ability to grow very quickly and spread to other tissues. How far the cancerous cells have spread is important for determining a patient's prognosis and treatment options. Lung cancer is typically divided into four different stages depending on how far the cancer has spread, with stage IV being the most serious.
Staging Process
To understand what stage IV lung cancer is, it helps to know how the stage of lung cancer is determined. The stage of a cancer describes the extent to which the cancerous cells have spread through the patient's body. For lung cancer, an X-ray of the chest as well as a CT scan is often used, the American College of Chest Physicians explains. Another test, called a positron emission test, may also be used. These tests allow doctors to get detailed images of not only the lungs but of other organs and bones, which can let them look for cancer cells in many different locations.
Identification
Stage IV lung cancer means that the cancerous cells are no longer confined to the lungs or to the chest and have spread to distant locations in the body. This process, known as metastasis, can allow the cells to travel anywhere in the body, but some of the most common sites of metastasis for lung cancer are the brain, bones and liver, the Mayo Clinic notes.
Symptoms
Patients with stage IV lung cancer typically have a variety of respiratory symptoms, including wheezing, a chronic cough which may produce blood, difficulty breathing and chest pain. Other symptoms are caused by the metastases. Patients who have lung cancer which has spread to the bones may have chronic bone pain. Liver metastases can result in abdominal pain and jaundice. If the cancer spreads to the brain, headache, trouble thinking and seizures can occur UpToDate states.
Treatment
Chemotherapy is usually the first treatment recommended for stage IV lung cancer, UpToDate states. Chemotherapy uses chemicals that are toxic to tumor cells in an effort to slow or stop the growth of the cancer. Chemotherapy is usually given in cycles, which encompasses the time needed for the chemotherapy to be administered and for the body to recover from the effects of chemotherapy. Targeted therapies, which involves a series of specially designed treatments, can interfere with cancer growth and spread may also be used. Brain metastases can also be treated using radiation.
Considerations
Stage IV lung cancer cannot be cured because it is impossible to eradicate the cancer from everywhere in the body. The main goal of stage IV lung cancer treatment is to relieve symptoms and prolong the patient's life. When deciding how to treat stage IV lung cancer, the benefits of different treatment approaches must be compared against the side effects of each kind of treatment as well as the patient's wishes. In some cases palliative care, which aims at reducing the patient's pain using pain killers and other treatments may be needed.
