Lung cancer can be a devastating diagnosis. Fortunately, there is a new diagnostic test now available for people at the highest risk of developing lung cancer. Jerry Barker, MD, a radiation oncologist at Baylor All Saints Medical Center at Fort Worth, answers some commonly asked questions about lung cancer.
What is lung cancer?
Lung cancer is a cancer that starts in the lungs. They typically arise from the cells that line airways in the lungs (known as ‘bronchi’, ‘bronchioles’, or ‘alveoli’). They often start with precancerous lung cells which over time begin to grow faster, ignore communications with other nearby cells, and even learn to cause new blood vessels to form nearby.
Eventually, these abnormal cells grow into a large enough collection of cells (a ‘mass’ or ‘tumor’) that they can be detected by an imaging test such as an x-ray. If left untreated, lung cancer can eventually spread (metastasize) to other parts of the body.
What causes lung cancer?
The chance of developing lung cancer is much higher in smokers than in non-smokers, and smoking is the leading risk factor for lung cancer. Even secondhand smoke increases the risk of developing lung cancer.
Exposure to high levels of radon, a naturally-occurring radioactive gas found in some areas in the United States, is also a risk factor for lung cancer.
Workplace exposure to asbestos fibers is a known risk factor, and this is why the government has been working to reduce the use of asbestos in commercial products for many years.
Researchers have suspected other possible causes of lung cancer, such as air pollution, arsenic, and diesel exhaust. Some patients do not develop lung cancer because they are exposed to a carcinogen like tobacco, but instead they have many family members with lung cancer and seem to have a genetic predisposition for lung cancer.
Can non-smokers develop lung cancer?
Many patients with lung cancer are former smokers, but even someone who has never smoked at all can get lung cancer. Exposure to secondhand smoke, radon, asbestos, and other carcinogens can cause lung cancer in a nonsmoker. There are also patients who do not have any exposure to carcinogens who may develop lung cancer because there is a genetic predisposition for lung cancer in their family. There are also apparently some patients who develop lung cancers randomly, or for reasons that physicians have not yet discovered.
What is this new diagnostic test for lung cancer?
For people at high risk of developing lung cancer, the most effective screening may be a low-dose CT scan, according to the latest research published from the National Lung Screening Trial in The New England Journal of Medicine.
Candidates for the screening include current and former smokers over the age of 55, people over 50 years old that have smoked the equivalent of one pack per day for 30 years or three packs a day for 10 years, and people with occupational exposure to other carcinogenic agents, including asbestos and diesel fumes. Important consideration for screening is whether the level of individual risk is high enough for screening to be of benefit. A physician referral is required.
People who are referred by their physician for being at high risk for lung cancer can take advantage of the low-dose CT lung cancer screening at Baylor Charles A. Sammons Cancer Centers at Dallas, Irving and Plano. The program in Irving has been in effect since the fall of 2012.
What are the symptoms of lung cancer?
When a small lung cancer grows, it can eventually cause symptoms that lead to its discovery. Symptoms can include a chronic cough, coughing up of blood, chest pain, shortness of breath, weight loss, and fatigue.
If a lung cancer continues to grow, it can spread to other parts of the body where it might cause bone pain, neurologic symptoms, or failure of an important organ to function correctly. If someone has any of these symptoms it does not mean that they definitely have lung cancer, but they should see their doctor right away so that the cause can be found and treated.
What is the treatment for lung cancer?
There are many treatments available today for patients with lung cancer, and this is an exciting area of research where new treatments are being developed often. Historically there have been three primary treatments for lung cancer: surgery, radiation therapy, and chemotherapy.
There are many variations of each of these treatments. Doctors decide which of the treatments are most likely to help a patient by using tests to determine the extent (or ‘stage’) of the cancer. It is common for a patient to meet with a thoracic surgeon, a radiation oncologist, a medical oncologist, and a pulmonologist—and together the team of specialists will help determine the best course of treatment for a particular patient.