What is Lung Cancer?

Lung cancer diagnoses strike over 224,000 people each year. Lung cancer typically forms within the lungs’ air passage linings, and often first presents as chest pain and a persistent cough that never abates. Many people develop severe shortness of breath as the disease progresses. Smoking is the leading cause of lung cancer, although genetics and exposure to other harmful chemicals may play a part in some cases. While radiations, surgery, and chemotherapy remain the most common treatments, recent developments give hope for new, more effective ways to deal with this disease. Lung Cancer Symptoms, Causes and Treatment

Lung cancer affects the lives of many thousands of people. It strikes one of the body’s most vital functions. With each breath, the lungs fill with air and the body takes in vital oxygen. Each exhale dispels carbon dioxide.

The number of annual lung cancer cases is quite daunting. In just 2014, close to 160,000 people died from lung cancer. Another 224,210 were diagnosed with the disease.1 Lung cancer remains one of the most common and deadliest cancers in the world.

Lung cancer usually forms in the cells that line the lungs’ air passages. Lung concern occurs in two main types:
  • Small cell lung cancer
    • The less common form, comprising about one out of every eight lung cancer diagnoses2
    • Often rapidly metastasizes to other parts of the body3
    • Non-small cell lung cancer
      • Accounts for about seven out of eight lung cancer cases
      • Spreads less rapidly than small-cell lung cancer4
“Small cell” and “Non-small cell” actually describe the relative appearance of how the two types of lung cancer look under when magnified under a microscope.

The symptoms of lung cancer vary from person to person. Chest pain and a cough that does not go away are two of the more common symptoms. Many also experience shortness of breath and wheezing. In some cases, patients cough up blood, while others just do not feel good. They may also have swollen lymph glands. Having repeated bouts of pneumonia is another warning sign. When the cancer spreads beyond the lungs, or metastasizes, people may feel extreme fatigue and have unexplained weight loss.5

Cigarette smoking remains the most common cause of lung cancer. However, not all lung cancer victims smoked. Nonetheless, smoking is implicated in about 90 percent of lung cancer cases in the United States.6 The good news is that when smokers quit the habit, their chances of developing lung cancer decrease.7

Other risk factors for lung cancer include exposure to:
  • Second hand smoke
  • Radon, a colorless, odorless gas often present in homes
  • Workplace materials such as asbestos, arsenic, and exhaust
Additionally, genetics sometimes play a role in developing lung cancer, especially if an immediate family member had lung cancer. Those who previously underwent cancer treatments involving radiation may have a higher risk of developing lung cancer.

Lung cancer survivability depends upon the cancer’s stage at the time of detection. For non-small cell lung cancer, health professionals use a staging system from “Hidden,” where cancer cells show up in sputum but imaging and bronchoscopy testing show no tumors, to Stage IV, involving tumors in both lungs, with spread of cancer throughout the body.8
For Stage I non-small cell lung cancer, the five-year survival rate is 45-49%. Stage II’s rate is about 30%, while Stage III has only a 5-14% five-year survival rate, and Stage IV, only 1%.9

Small Cell lung cancer has only two stages, limited, where it is on one side, and extensive, where it has spread throughout one or both lungs and elsewhere in the body.10 The five-year survival rates are lower than those for non-small cell lung cancer.<

Radiation, chemotherapy, and surgery are the most common treatments for lung cancer. Before during, and after treatment, many patients require oxygen devices to compensate for loss of lung function. Additionally, many innovative treatment options are on the horizon. Genetically engineered immunotherapy, virus therapy, targeted therapies designed to work with chemotherapy to damage cancer DNA.


1 http://www.cancer.gov/cancertopics/lung

2 http://www.cancer.gov/cancertopics/

3 http://www.mayoclinic.org/diseases-conditions/cancer/expert-answers/cancer/

4 http://www.cancer.gov/cancertopics//lung/page4

5 http://www.cdc.gov/cancer/lung/basic_info/symptoms.htm

6 http://www.cdc.gov/lung-cancer/risk_factors.htm

7 http://www.cdc.gov/lung-cancer/risk_factors.htm

8 http://www.cancer.gov/treatment/non-small-cell-lung/

9 http://www.cancer.org/non-small-cell-lung-cancer-survival-rates

10 http://www.cancer.org/small-cell-lung-cancer-staging

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