Smoking is the primary cause in most lung cancer diagnoses, but about 4 percent of cases are caused by asbestos exposure. SEER data shows asbestos-related lung cancer is estimated to kill more than 6,000 Americans per year. It claims the most lives of all asbestos-related illnesses.
Lung cancer is the leading cause of cancer death in the United States. It kills more Americans each year than breast, prostate and colon cancer combined.
Medical researchers first made a probable causal relationship between asbestos exposure and lung cancer in 1935. Seven years later, a member of the National Cancer Institute confirmed asbestos as a cause of lung cancer.
Study after study continued to show the cause-effect relationship of asbestos and lung cancer. In 1986, the Occupational Safety and Health Administration (OSHA) proclaimed lung cancer as the greatest risk for Americans who work with asbestos.
These symptoms typically only arise once the cancer reaches a late stage of development. It is rare for lung cancer to be diagnosed in an early stage unless a patient is regularly screened. Patients with a history of asbestos exposure should seek regular screening for asbestos-related diseases.
The diagnostic process begins with imaging scans such as X-rays and CT scans. If the patient is coughing up sputum, which is a mixture of saliva and mucus, a sputum cytology test might reveal the presence of cancer cells.
A pathologist must examine a sample of suspicious tissue under a microscope to confirm a lung cancer diagnosis. The biopsy sample may be extracted through a long needle or with a special tool called a bronchoscope. A bronchoscope is passed down the throat and into the airways of the lungs.
When a person inhales asbestos, microscopic fibers of the toxic mineral can become lodged in their lung tissue. Over many years, these fibers may cause enough genetic and cellular damage to cause lung cells to turn cancerous.
Whether someone develops lung cancer depends on several factors. These factors include overall health, genetics, smoking history and the duration and intensity of the asbestos exposure.
All asbestos-related diseases have a long latency period from the time of initial exposure to the onset of symptoms. Asbestos-related lung cancer typically takes between 15 and 35 years to develop. The latency period depends on the level of exposure to asbestos. It also depends on whether the lungs are affected by additional carcinogens such as those commonly found in cigarette smoke.
U.S. companies manufactured a wide variety of asbestos-containing products from the late 1800s up until the 1980s. The mineral was mined at many sites across North America. The mining and commercial use of asbestos is now highly regulated in the United States.
Some chemical, construction and automotive companies still use asbestos. The mineral has not been banned in the U.S.
Because of the long latency period of asbestos-related lung cancer, most cases diagnosed today were caused by asbestos exposure that occurred decades ago before safety regulations existed. Occupational asbestos exposure is the primary cause of asbestos-related disease. The most at-risk professions involve mining, construction, heavy industry, shipbuilding and firefighting.
Veterans are also a high-risk group for asbestos-related lung cancer. This is because of the military’s heavy use of asbestos products in bases, vehicles and ships.
There are two primary forms of lung cancer: Small cell and non-small cell. Certain subsets of non-small cell lung cancer (NSCLC) may be less aggressive than the small cell lung cancer variety. Non-small cell lung cancer is definitely a more common malignant disease, accounting for more than 85 percent of all lung cancer cases.
Small cell lung cancer (SCLC) makes up 10-15 percent of cases and is more difficult to treat. In the common clinical cases where small cell lung cancer has spread outside of the confines of the chest, it is almost never a curable disease. Asbestos exposure can cause any one of the various types and subtypes of lung cancer.
Typically originating in the bronchi near the center of the chest, SCLC is aggressive and spreads quickly throughout the body. The cancer can disperse from its initial location before presenting any symptoms. It can spread to other parts of the body such as the lymph nodes, bones, liver, adrenal glands or brain.
Unfortunately, surgery is rarely an option with SCLC because of this factor. Doctors instead rely on chemotherapy that attacks cancer cells all throughout the body. In cases where small cell lung cancer is limited to the thorax (chest) , chemotherapy and radiation are often used together.
Karen Selby joined Asbestos.com in 2009. She is a registered nurse with a background in oncology and thoracic surgery and was the director of a tissue bank before becoming a Patient Advocate at The Mesothelioma Center. Karen has assisted surgeons with thoracic surgeries such as lung resections, lung transplants, pneumonectomies, pleurectomies and wedge resections. She is also a member of the Academy of Oncology Nurse & Patient Navigators. Read More