Understanding Lung Cancer

Lung cancer begins in the lungs and develops when cells in the lung begin to grow out of control. Normal cells grow, divide and die as the body needs them.

Cancer cells act differently from normal cells because of damage or a change in the cells' DNA (genes that tell the cells what to do).Cancer cells grow at an accelerated rate but do not die. Instead, they continue to grow and form a group of abnormal cells called a tumor.

What are the signs or symptoms of lung cancer?
There can be several symptoms of lung cancer including:
  • cough that won't go away
  • coughing up blood
  • chest, back or shoulder pain
  • shortness of breath
  • wheezing
  • hoarseness
  • being tired
  • weight loss

If you or someone you know has symptoms or may be at risk for lung cancer, talk with your health care provider about your concerns.

What are the causes of lung cancer?
Smoking is the leading cause of lung cancer and is responsible for 87% of lung cancer cases. Exposure to secondhand smoke can also cause lung cancer. It is estimated that 3,000 lung cancer cases each year are caused by exposure to secondhand smoke. In addition, exposure to radon, a naturally occurring, odorless, colorless gas in your home can cause lung cancer. Radon causes an estimated 20,000 lung cancer deaths each year.

How can you protect yourself from developing lung cancer?
  • Do not smoke. If you smoke or use tobacco in any form, quit. As soon as you quit, your body will begin to repair the damage done by smoking.
  • Get your home tested for radon. Simple, inexpensive test kits are available at most home improvement stores.
  • Avoid secondhand smoke. Make your home and car smoke-free. Encourage family, friends and co-workers to quit smoking.

What are the types of lung cancer?
There are two main types of lung cancer; non-small cell lung cancer and small cell lung cancer. Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for about 87% of all lung cancers. There are three kinds of non-small cell lung cancer:
  • Adenocarcinoma accounts for 40% of all NSCLC. This type of lung cancer is usually found in the outer regions of the lung. There is also a rare form of adenocarcinoma, called bronchioalveolar carcinoma (BAC) that is on the rise worldwide. BAC spreads throughout the lung, unlike the more common types that form single tumors. The cause of BAC is not known. Although people who smoke can get BAC, it often occurs in people who have never smoked.
  • Squamous cell carcinoma accounts for 25-30% of NSCLC. This type is usually found near the bronchus, close to the center of the chest. It is also known as epidermoid carcinoma and is usually associated with tobacco smoke exposure.
  • Large cell carcinoma accounts for about 10-15% of NSCLC. It grows quickly and may appear in any part of the lung.
Small cell lung cancer (SCLC) tends to grow and spread more rapidly and may cause symptoms sooner than non-small cell cancers. This is a less common type of lung cancer.

What if I have been diagnosed with lung cancer?
After the type and stage of lung cancer is identified, you and your family can discuss treatment options with your team of health care professionals. Treatment plans are based on the type and stage of lung cancer and the patient's overall health. Many people benefit from a combination of treatments including:
  • Surgery to remove the tumor
  • Chemotherapy (medication that kills or shrinks the tumor)
  • Radiation therapy (X-rays thatdamage cancer cells)
  • Research studies
Please also see this free webinar developed by LungCAN, "You have just been diagnosed with lung cancer – now what?"


How can I find lung cancer clinical trials in my area?

Respiratory Health Association of Metropolitan Chicago offers links to local clinical trials in lung cancer and other lung diseases as resource for people seeking information about these opportunities. For more information, visit our Clinical Trials page.

For more information, visit our Lung Cancer Library.