Lung Cancer

What is lung cancer? Lung cancer starts when abnormal cells grow out of control in the lung. They can invade nearby tissues and form tumors. Lung cancer can start anywhere in the lungs and affect any part of the respiratory system. The cancer cells can spread, or metastasize, to the lymph nodes and other parts of the body.

How is lung cancer diagnosed? Your doctor will check your symptoms and ask questions about whether you smoke or have been exposed to another person's smoke or to any cancer-causing substances. He or she will also ask about your medical history, including any history of cancer in your family. This information will help your doctor decide how likely it is that you have lung cancer and whether you need tests to be sure.

What causes lung cancer? Most lung cancer is caused by smoking. Secondhand smoke also can cause lung cancer. Lung cancer is the leading cause of cancer deaths. Being exposed to arsenic, asbestos, radioactive dust, or radon can increase your chances of getting lung cancer. People who are exposed to radiation at work or elsewhere have a higher chance of getting lung cancer.

Lung cancer is usually first found on a chest X-ray or a CT scan. More tests are done to find out what kind of cancer cells you have and whether they have spread beyond your lung. These tests help your doctor and you find out what stage the cancer is in. The stage is a rating to measure how big the cancer is and how far it has spread. Exams and Tests To determine whether lung cancer may be causing your respiratory symptoms, your doctor will evaluate your:

What are the symptoms?

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Early lung cancer doesn't usually cause any symptoms. This is why it's not usually found early.

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What Happens Lung cancer may cause breathing or heart problems such as:

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Pleural effusion, which is the buildup of fluid between the outer lining of the lungs and the chest wall. This is a common condition with lung cancer. Coughing up large amounts of bloody sputum. Collapse of a lung (pneumothorax). Blockage of the airway (bronchial obstruction). Recurrent infections, such as pneumonia. Pericardial effusion, which is the buildup of fluid in the space between the heart and the sac around the heart (pericardium). This condition is not common with lung cancer.

As lung cancer grows, it may spread (metastasize) to other parts of the body. Lung cancer is classified in stages that are determined by the size of the cancer and how far it has spread within the lung, to nearby tissues, or to other organs. Your doctor determines the stage of your lung cancer by gathering information from a variety of tests, including bone scans, PET scans, CT scans, and X-rays. The stage of your cancer is one of the most important factors in choosing an effective treatment. The long-term outcome (prognosis) for lung cancer depends on how much the cancer has grown and spread. Experts talk about prognosis in terms of "5-year survival rates." The 5-year survival rate means the percentage of people who are still alive 5 years or longer after their cancer was discovered. Because lung cancer is often diagnosed at an advanced stage, only 16% of people live 5 or more years after being diagnosed. 1 It is important to remember that these are only averages. Everyone's case is different, and these numbers do not necessarily show what will happen to you.

Medical history, including your smoking history and any symptoms you have now. Exposure to environmental and work substances. Family history of cancer.

Initial exams and tests for suspected lung cancer include:

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Medical history to determine your risk factors for developing lung cancer. Physical examination to find any lung problems or swollen lymph nodes. Chest X-ray to look for any abnormalities that may be causing your symptoms, such as pneumonia or a lung mass (tumor). Complete blood count (CBC) to see whether you have abnormal values of red blood cells, white blood cells, or platelets. Calcium, creatinine, alkaline phosphatase, and lactic acid dehydrogenase to determine electrolyte and liver function. These tests are likely to have abnormal values if cancer is present and has spread to other tissue or body organs.

If your medical history, physical examination, or chest X-ray suggest that lung cancer is present, your doctor may recommend other tests, such as:

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CT scan of the lungs, sometimes with transthoracic needle aspiration biopsy (TNAB) of a lung nodule. A needle biopsy uses a needle inserted through the chest wall to remove a sample of lung tissue (biopsy). This usually is done if the abnormal lung tissue is located close to the chest wall. Imaging procedures such as ultrasound or fluoroscopy may also be used to help guide the needle to the right spot. Sputum cytology to evaluate the type of any abnormal cells that are present in your mucus. Thoracentesis to take a sample of the fluid around your lungs to evaluate the type of any abnormal cells. Thoracentesis is done if you have a large collection of fluid around your lung (pleural effusion). Thoracentesis is sometimes used to find out why you have fluid collecting

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around your lung. Other times it is just to remove the fluid and make it easier for you to breathe. Bronchoscopy to take a biopsy of cells from your airway. Lung biopsy to evaluate the type of any abnormal cells.

Can you prevent lung cancer? Lung cancer is one of the easiest cancers to prevent because most lung cancer is caused by smoking. So it is important to stop smoking —or to stop being around someone else’s smoke. Even if you have smoked a long time, quitting can lower your chances of getting cancer. If you already have lung cancer, quitting makes your treatment work better and can help you live longer. What Increases Your Risk Risk factors for lung cancer include:

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Tobacco use. Smoking and chewing tobacco are related to developing lung cancer, as well as to cancer of the mouth and throat. Over 85% of lung cancers are related to smoking. 2 More than half of the people who are newly diagnosed with lung cancer are former smokers. Smoking unfiltered, high-tar cigarettes may put you at a higher risk than smoking filtered or low-tar cigarettes, although this has not been proved. The risk of developing lung cancer increases: o The longer you smoke. o The more cigarettes you smoke each day. Exposure to tobacco smoke, such as living with a smoker. If you live with a smoker, you have 2 to 3 times the risk for lung cancer compared with a person who lives in a nonsmoking environment. 5 About 25% of nonsmokers who develop lung cancer probably get it from being exposed to secondhand smoke. 3 Marijuana use. Smoking one marijuana cigarette, or a joint, may affect the lungs as much as smoking a pack of cigarettes. 8 Exposure to certain chemicals, such as arsenic, asbestos, radioactive dust, or radon. Radiation exposure from occupational, medical, or environmental sources.

How is it treated? Treatment for lung cancer includes surgery, anti-cancer medicines (chemotherapy), radiation, or a mix of all three. It depends on what type of cancer you have and how much it has spread. Few lung cancers are found in the early stages when treatment is most effective. It can be very scary to learn that you may have lung cancer. Talking with your doctor or joining a support group may help you deal with your feelings. Having support from family and friends can help a lot. And staying as active as possible will also help. Less than half of people who get lung cancer live 1 more year after the cancer is found. And only about 16 out of 100 people with lung cancer live for 5 or more years. 1 It’s important to remember that

everyone’s case is different and that these numbers may not show what will happen in your case.