Smoking is the primary cause in most lung cancer diagnoses, but about 4 percent of cases are traced back to asbestos exposure. SEER data shows asbestos-related lung cancer is estimated to kill more than 6,000 Americans per year, making it the most lethal of all asbestos-related illnesses.
Lung cancer is the leading cause of cancer death in the United States, killing 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, and in 1986, the Occupational Safety and Health Administration (OSHA) proclaimed lung cancer as the greatest risk for Americans who work with asbestos.
Whether lung cancer is associated with asbestos exposure or another cause, it presents the same general symptoms:
These symptoms typically only arise once the cancer reaches a late stage of development, so 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 can reveal the presence of cancer cells.
To make a definitive diagnosis of cancer, however, a pathologist usually has to examine a sample of suspicious tissue under a microscope. The biopsy sample may be extracted through a long needle or with a special tool called a bronchoscope that is passed down the throat and into the airways of the lungs. Occasionally, lung cancer can also be diagnosed by a cytological evaluation of a patient’s sputum.
Treatment options include surgery, chemotherapy, radiation therapy and immunotherapy, and experimental approaches may be available through clinical trials. A patient’s treatment plan is determined in large part by the stage and histological type of the cancer as well as the patient’s overall health.Learn more about treatment for asbestos-related lung cancer
When a person inhales asbestos, microscopic fibers of the toxic mineral can become permanently lodged in the person’s lung tissue. Over many years, these fibers may cause enough irritation and cellular damage to generate cancer cells that grow into a tumor.
Whether someone develops lung cancer or any other asbestos-related disease depends on their overall health, genetics 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 between15 and 35 years to develop. The extraordinarily long latency periods depends on the level of exposure to asbestos and whether the lungs are affected by additional carcinogens such as those commonly found in cigarette smoke.
Both diseases take decades to develop but only months to spread to distant organs. The two forms of cancer involve similar diagnostic procedures, but they differ in risk factors, physical characteristics and treatment techniques.Learn more about mesothelioma and lung cancer
U.S. companies manufactured a wide variety of asbestos-containing products from the late 1800s up until the 1980s, and 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 and banned completely in most developed nations.
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, with the most at-risk professions involving mining, construction, heavy industry, shipbuilding and firefighting.
Veterans are also a high-risk group for asbestos-related lung cancer because of the military’s heavy use of asbestos products in bases, vehicles and ships.
The risk of lung cancer is much higher among asbestos-exposed smokers because smoking impairs the lungs’ ability to dispel asbestos fibers. Smokers who have been exposed to asbestos should stop smoking immediately and seek annual screenings for lung cancer.Learn more about asbestos-related diseases and smoking
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.
There are three primary subtypes of NSCLC distinguishable by the appearance and chemical makeup of their cells:
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, rapidly spreading 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.
The prognosis for someone with lung cancer depends on the type and subtype of the disease, the patient’s overall health and how far the cancer has spread by the time it has been diagnosed. In the United States, about 18 percent of lung cancer patients survive more than 5 years after diagnosis.Learn more about asbestos-related lung cancer prognosis
The Helsinki Criteria were established in 1997 to help doctors determine when respiratory diseases are caused by asbestos. For a lung cancer case to be diagnosed as asbestos related, it must fit two criteria:
The lung cancer must have developed at least 10 years after the initial exposure to asbestos.
One of the following must be documented:
The presence of asbestosis is a reliable diagnostic marker that a patient was exposed to asbestos enough to develop lung cancer. Asbestosis and lung cancer are commonly associated because the risk for both rises in parallel as asbestos fibers accumulate in lung tissue.Learn more about asbestosis
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