Lung cancer is abnormal cell growth that originates in the tissues that line the lung’s air passages. As abnormal lung cells grow and multiply, they form into a tumor and disrupt the function of the lungs, to provide oxygen to the body via blood circulation. It is the second most commonly diagnosed cancer, and it is the leading cause of cancer death for both men and women1.
Credit: American Cancer Society
What different types of lung cancer exist?
There are several types of lung cancer that affect the different cells of this organ. Read more about the types of lung cancer at: http://www.cancer.org/cancer/lungcancer/index
What are the symptoms of lung cancer?
- Coughing, especially if it becomes intense
- Pain in the chest, shoulders or back
- Shortness of breath
- Changes in the voice or hoarseness
- Harsh sounds with each breath
- Recurrent lung problems, such as bronchitis or pneumonia
- Coughing up phlegm or mucus, especially with blood
- Loss of appetite or unexpected weight loss
- Muscle wasting
- Headaches, bone or joint pains
- Bone fractures not related to accidental injury
- Neurological symptoms, such as memory loss
- General weakness
- Blood clots
How is lung cancer diagnosed?
Physical examinations are used to evaluate the swollenness of the lymph nodes in the neck and collarbone area. Lymph node swelling may indicate the presence of lung cancer. Physical exams for lung cancer will also include chest examinations, which use a stethoscope to listen for abnormal breathing patterns, a symptom of lung cancer presence.
Imaging tests use x-rays, magnets, sound waves or radioactive chemicals to produce pictures of the inside of the body. For lung cancer, these tests may include chest x-rays, computed tomography (CAT or CT) scans, positron emission tomography (PET) scans, magnetic resonance imaging (MRI) scans and bone scans.
Sputum cytology is an examination of mucus or phlegm coughed up from the lungs to check for the presence of cancerous cells.
Bronchoscopy uses a lighted, flexible tube to view the inside of the lungs. It can pass through the nose or the throat into the main airways of the lungs. If there is abnormal activity in the lungs, the end of the tube has special tools to remove samples for further evaluation.
Biopsies are the removal of a portion of a tumor so it can be examined under the microscope. This is the only way to differentiate between lung cancer and other lung diseases.
What are the different stages of lung cancer?
Small Cell and Non-Small Cell Lung Cancers are staged separately. The most widely used staging systems for lung cancer are the TNM systems maintained by the American Joint Committee on Cancer (AJCC).
Though staged separately, these lung cancers share the system used to describe the growth and spread of SCLC and NSCLC. The TNM system for SLC and NSCLC is based on 3 key pieces of information:
- T indicates the size of the main (primary) tumor and whether it has grown into nearby areas.
- N describes the spread of cancer to nearby (regional) lymph nodes. Lymph nodes are small bean-shaped collections of immune system cells to which cancers often spread before going to other parts of the body.
- M indicates whether the cancer has spread (metastasized) to other organs of the body. (The most common sites are the brain, bones, adrenal glands, liver, kidneys, and the other lung.)
What are the treatments of lung cancer?
This lung cancer treatment information does not outline the particular treatment(s) a patient will receive. Rather, it provides general information about the typical treatments used for this type of cancer.
Primary treatment options:
- Surgery is the removal of a part or the entirety of a cancerous lung. Surgery offers the greatest chance for significant patient survival for some lung cancer types, especially early stage (I and II) small and non-small lung cancers, which have not yet spread to other parts of the body and nearby lymph nodes.
- Chemotherapy employs drugs to treat cancer. These drugs are injected into the bloodstream and they circulate to destroy cancer cells throughout the body. Chemotherapy is primarily used to treat early non-small cell lung cancer and as a secondary treatment for small cell lung cancer.
- Radiation therapy uses high-energy rays or particles to kill cancer cells. Radiation therapy is commonly used to treat non-small cell lung cancer (stages 2 and 3) and small cell lung cancer.
Secondary treatment options:
- Chemotherapy regimens are an experimental form of chemotherapy that combines different existing chemotherapy drugs and explores their effectiveness in treating lung cancer together. Researchers currently are performing clinical trials in testing these new combinations of drugs to find out if they will work better than the standard chemotherapy practice..
- Targeted therapies are drugs that restrict the growth of lung cancer cells and protect healthy cells from damage. They are most often used for advanced lung cancers, either along with chemotherapy or by themselves.
- Photodynamic therapy is a treatment that uses drugs that are responsive to particular types of light. When light activated drugs are exposed to a specific wavelength of light, they produce a form of oxygen that kills cancer cells in particular areas of the lungs.
- Lung cancer vaccines use the body’s immune system defend against diseases by using benign lung cancer cells that still have traits that are recognized as foreign to the immune system. When the body recognizes cancerous cells as a foreign entities it begins to attack these cells and cells sharing a similar structure. The vaccine is not promising as a preventative measure but shows effectiveness in treating existing cancer.
What are the risk factors of lung cancer?
- Smoking: The largest risk for developing lung cancer is smoking tobacco. Nearly 87% of all lung cancer cases in the U.S are smoking-related. Exposure to second-hand smoke increases the risk of developing lung cancer by 20-30%.
- Asbestos exposure: Inhalation of asbestos, a tiny fiber-like rock that was used for insulation of buildings and in a variety of consumer products, is linked to an increase in lung cancer rates.
- Radiation exposure: Having X-rays to the chest can increase chances of lung cancer, especially for people who smoke.
- Tuberculosis: Tuberculosis can cause scarring in the lung walls, which can be a risk factor towards lung cancer.
- Radon exposure: Inhalation of radon gas is correlated with higher lung cancer incidences.
- Industrial substance exposure: Exposure to uranium, beryllium, vinyl chloride, nickel chromates, coal products, mustard gas, chloromethyl ethers, gasoline and diesel exhaust may increase the chance of developing lung cancer.
How can I prevent getting lung cancer?
- Ceasing or never starting to smoke tobacco products.
- Avoiding second-hand smoke, asbestos and radon.
- If you are already at risk of lung cancer, talk to your doctor about screening techniques to promote early detection.