The most common type of lung cancer, non-small cell lung cancer accounts for roughly 80 percent of all lung cancer diagnoses. NSCLCs are actually classified into three different subcategories:
- squamous cell carcinomas
- large cell carcinomas
Squamous cell carcinomas originate along the respiratory tract, specifically in the thin, flat cells that line the respiratory passages.
Adenocarcinoma is the most commonly diagnosed form of lung cancer, accounting for 30-40 percent of all cases. This occurs when the cells that form the lining of the lungs become cancerous.
Large cell carcinomas make up about 10 percent of all cases, and are those that appear large and abnormal upon examination under a microscope.
What are the risks for lung cancer?
According to the Lung Cancer Alliance, a nonprofit dedicated to providing support and advocacy for those with or at risk for lung cancer, more than 85 percent of lung cancer cases are caused by smoking. Simply put, those who are still smoking are putting themselves at a heightened and ultimately unnecessary risk of lung cancer. Of the more than 4,000 chemicals contained in cigarette smoke, the majority have been linked to causing cancer. For those who are trying to quit, research has indicated that a person who quits smoking will have the same risk as a person who never smoked 15 years after quitting. That means a smoker who quits at 30 will, by the time he or she turns 45, have the same risk of lung cancer that a fellow 45-year-old who never smoked has.
But smoking isn't the only thing that increases a person's risk for lung cancer. One additional risk factor is exposure to radon, a carcinogen and byproduct of radium that is present in both indoor and outdoor air. This heightens the importance of having a home routinely tested for radon, as prolonged radon exposure increases the risk for lung cancer.
Other potential causes of lung cancer include exposure to asbestos (which can also lead to mesothelioma, a cancer that affects the lining of the lungs and stomach) and exposure to cancer-causing agents in the environment.
To learn more about lung cancer or for help with quitting smoking, visit the National Cancer Institute Web site at www.cancer.gov.