Lung Cancer Basics

What is lung cancer? Lung cancer is cancer that begins in your lungs. Cancer that started somewhere else, then spread to your lungs, is called metastatic cancer (from the original site) and not lung cancer.

What are the types of lung cancer? There are 2 main types of lung cancer: (1) non-small cell and (2) small cell. Non-small cell lung cancer is sometimes subcategorized further (squamous cell, adenocarcinoma, large cell, or a combination), based upon the pathologists microscopic interpretation. These two types account for over 95% of lung cancers.

How common is lung cancer? Lung cancer remains the leading cause of cancer death in the US for both men and women. (Over 20 years ago, lung cancer deaths surpassed breast cancer deaths in women in the US). Lung cancer currently accounts for about 26% of all female cancer deaths and about 31% of cancer deaths in men. In fact, in the US, lung cancer deaths outnumber the deaths from the four next most common cancers combined (colon, breast, pancreas and prostate). For 2009, it is estimated that there will be 219,440 new lung cancers diagnosed in the US (116,090 among men and 103,350 among women). Lung cancer is usually seen in those over the age of 60 and is rare under 45.

What causes lung cancer? Cigarette smoking is the leading cause of lung cancer- the more you smoke and the younger you start, the higher the risk. Secondhand smoke (breathing in smoke of others) also increases your risk of lung cancer. According to the American Cancer Society, 3,000 die each year in the US from lung cancer related to only secondhand smoke. Lung cancer can also occur (although very rarely) in never smokers (without secondhand exposure).

Other causes of lung cancer include: radon, asbestos, arsenic, beryllium, nickel, silica, mustard gas, radiation, and chloromethyl ethers. There is a higher lung cancer incidence in those with a close blood relative with lung cancer.

What are the symptoms of lung cancer? The symptoms of lung cancer include:

  1. persistent cough
  2. coughing up blood
  3. shortness of breath
  4. unexplained weight loss
  5. loss of appetite
  6. chest pain
  7. undue fatigue

Other symptoms associated with lung cancer include:

  1. bone pain
  2. hoarseness
  3. facial swelling
  4. drooping eyelid
  5. weakness
  6. paralysis or unsteadiness of gait

These are important symptoms, so see your doctor if you experience any of these, especially if you smoke.

What happens if I have these symptoms? When you see your doctor, he or she will likely take a thorough history and physical examination. Afterwards, your doctor may run additional tests, including:

  1. chest x-ray (regular lung x-ray)
  2. sputum test (sample of the stuff you cough up from deep in your lungs)
  3. blood work
  4. CT scan (computerized x-ray)
  5. PET scan (computerized scan using an injection of special glucose to look for areas of potential cancer)

Depending upon the findings, your doctor may need to perform a biopsy- removing some tissue from the lung for examination by a pathologist under the microscope. This can be done by several different methods, including:

  • Fiberoptic bronchoscopy (thin, lighted flexible tube inserted through the nose or mouth)
  • Percutaneous biopsy (from the outside, directly through the skin)
  • VAT (video scope inserted through small incisions, under general anesthesia)
  • Open biopsy (larger incision, under general anesthesia)

If I have lung cancer? After your doctor discovers lung cancer, he or she will need to do “staging” tests, to find out the extent or spread of the cancer. Your doctor might send you to an oncologist (cancer doctor) or pulmonologist (lung doctor). Treatment of lung cancer depends upon the type and the extent. It also depends upon your age and overall health.

What can I do to prevent lung cancer? First and foremost, if you smoke, quit! It’s never too late to stop smoking. Avoid secondhand smoke exposure. Eating a diet rich in fruits and vegetables may help reduce your risk. If you live in an area with underground basements, have your house tested for radon. Avoid exposures to other known lung carcinogens.

References:

American Cancer Society
Alberg AJ, Ford JG, Samet JM; American College of Chest Physicians. Epidemiology of lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition). Chest. 2007;132:29S-55S.
CancerCare
National Cancer Institute
American Lung Association