Symptoms, Diagnosis & Risk Factors
The signs and symptoms of lung cancer can take years to develop. They are often mistaken for less serious symptoms thought to be related to tobacco usage alone. These symptoms may include any of the following:
Smokers and Ex-Smokers
- Persistent cough that lasts for more than two weeks
- Chest infection that doesn’t get better
- Recurrent pneumonia or bronchitis
- Shortness of breath
- Coughing up blood
- Chest discomfort
- Loss of appetite
- Loss of weight
- Neck and facial swelling
- Aching joints
Most lung cancers are diagnosed when tumors grow and begin to interfere with lung function. Fluid can collect in the lung or around the lung.
There are several tools used to diagnose lung cancer. A doctor may order a chest X-ray, as well as a sputum cytology (a microscopic examination of the mucus in the lungs).
A biopsy must be performed in order to confirm the presence of lung cancer. A number of methods can be used.
- In a bronchoscopy, a thin, lighted tube is inserted in the mouth or nose and down the windpipe into breathing passages.
- In a needle aspiration, a needle is inserted through the chest wall into the tumor, usually under the guidance of X-ray imaging.
- In a thoracentesis, a needle is used to remove fluid surrounding the lungs.
- In a thoracotomy, the chest is surgically opened.
- In a bone marrow biopsy, a needle is used to remove a small piece of bone, usually from the back of the hip bone.
If the biopsy confirms that cancer is present, your doctor will need to determine whether the disease has spread, a process called staging.
Nearly 90 percent of all lung cancer cases are related to tobacco use, and approximately half of all continuing smokers will die from a disease caused by smoking. Cigarette smoke contains more than 4,000 chemicals, many of them cancer-causing substances (carcinogens) that damage the cells in the lungs. Over time the damaged cells become cancerous. Lung cancer occurs most frequently among people over 50 who have smoked for many years. Former tobacco users who stop smoking lessen their risk of developing a lung cancer over time. We can help you quit smoking with our Smoke-Free Life Program. Too often, however, cancer will still develop in former smokers, years after they have kicked the habit.
Other risk factors include exposure to radon, asbestos and some organic chemicals; radiation exposure from occupational, medical or environmental sources; air pollution; tuberculosis; and exposure to certain industrial substances, such as arsenic. Tobacco use combined with one of these other risk factors can increase the risk of developing lung cancer in an exponential manner.