Different factors increase or decrease the risk of lung cancer.
                    		Anything that increases your chance of getting a disease is called a risk factor. Anything that decreases your chance of getting a disease is called a protective factor.   For information about risk factors and protective factors for lung cancer, see the PDQ summary on Lung Cancer Prevention.
        				
        				
		                    Key Points
		                    - Screening tests have risks.    - The risks of lung cancer screening tests include the following:          - Finding lung cancer may not improve health or help you live longer.     - False-negative test results can occur.     - False-positive test results can occur.     - Chest x-rays and low-dose spiral CT scans expose the chest to radiation.     -  Talk to your doctor about your risk for lung cancer and your need for screening tests.
		                
		                
		                    Screening tests have risks.
		                    Decisions about screening tests can be difficult. Not all screening tests are helpful and most have risks. Before having any screening test, you may want to discuss the test with your doctor. It is important to know the risks of the test and whether it has been proven to reduce the risk of dying from cancer.
		                
		                
		                    The risks of lung cancer screening tests include the following:
		                    Finding lung cancer may not improve health or help you live longer.    Screening may not improve your health or help you live longer if you have lung cancer that has already spread to other places in your body.     When a screening test result leads to the diagnosis and treatment of a disease that may never have caused symptoms or become life-threatening, it is called overdiagnosis. It is not known if treatment of these cancers would help you live longer than if no treatment were given, and treatments for cancer may have serious side effects. Harms of treatment may happen more often in people who have medical problems caused by heavy or long-term smoking.       False-negative test results can occur.    Screening test results may appear to be normal even though lung cancer is present. A person who receives a false-negative test result (one that shows there is no cancer when there really is) may delay seeking medical care even if there are symptoms.       False-positive test results can occur.    Screening test results may appear to be abnormal even though no cancer is present. A false-positive test result (one that shows there is cancer when there really isn't) can cause anxiety and is usually followed by more tests (such as biopsy), which also have risks. A biopsy to diagnose lung cancer can cause part of the lung to collapse. Sometimes surgery is needed to reinflate the lung. Harms of diagnostic tests may happen more often in patients who have medical problems caused by heavy or long-term smoking.        Chest x-rays and low-dose spiral CT scans expose the chest to radiation.     Radiation exposure from chest x-rays and low-dose spiral CT scans may increase the risk of cancer. Younger people and people at low risk for lung cancer are more likely to develop lung cancer caused by radiation exposure. .        Talk to your doctor about your risk for lung cancer and your need for screening tests.    Talk to your doctor or other health care provider about your risk for lung cancer, whether a screening test is right for you, and about the benefits and harms of the screening test. You should take part in the decision about whether a screening test is right for you. (See the PDQ summary on Cancer Screening Overview for more information.)