Asbestos Lung Cancer
Asbestos is a known carcinogen; exposure to it can cause lung cancer and pleural mesothelioma. The human body cannot break down asbestos fibers when inhaled. Instead, the fibers embed in the lung tissue. Lung cancer forms in the cells, while pleural mesothelioma forms in the lining of the lungs, known as pleura.
Medically Reviewed By:
Patricia Shelton, M.D.
Medically Reviewed By:Patricia Shelton, M.D.
What Is the Difference between Asbestos-Related Lung Cancer and Mesothelioma?
Lung cancer forms in the cells of the lung itself, while malignant mesothelioma forms in the lining around certain organs. Pleural mesothelioma develops in the lining of the lungs, known as the pleura.
Some epidemiology studies have estimated that asbestos-related lung cancer causes twice as many deaths per year as mesothelioma, but it’s often difficult to determine the cause of particular lung cancer cases since other factors besides asbestos exposure increase risk for this disease.
Asbestos exposure can also lead to other asbestos-related diseases, such as asbestosis. This is a lung disease in which the presence of asbestos fibers leads to scarring throughout the lung, which eventually interferes with its function and makes breathing difficult. Although asbestosis is not a type of cancer, it’s an indication that a patient had significant asbestos exposure and is at risk for asbestos-related cancers.
How Does Asbestos Cause Lung Cancer?
Asbestos fibers are very tiny. When they’re present in the air, they can’t be seen or even smelled. When a person inhales them, the asbestos fibers can become embedded in the lung tissue.
It’s very difficult to break down asbestos; this is why it was so useful in certain industrial applications. When the fibers enter the lung tissue, the body mounts an immune response to try and remove them. However, the fibers are so stable that they cannot be broken down. The body mounts a stronger and stronger immune response, which is sustained over many years. This damages the surrounding tissues, causing changes in the DNA of lung cells that lead those cells to become cancerous.
People with a history of occupational asbestos exposure are at risk for developing asbestos-related diseases or cancer. Their family members may also be at risk since asbestos fibers can be carried home on a worker’s clothing, hair or skin.
There are two different types of asbestos. Serpentine (also known as chrysotile) asbestos tends to break apart more easily into smaller particles and fibers, and the fibers are curly. Amphibole asbestos (a group that includes the minerals amosite, crocidolite, tremolite, anthophyllite and actinolite) tends to remain in longer fibers, and the fibers are straight.
Both types are associated with lung cancer. This is because the lung tissue is directly exposed to asbestos fibers in the air, so it’s easy for any shape of asbestos fiber to embed itself into the lung tissue. However, the straighter and longer amphibole asbestos fibers are more likely to work their way through the lung tissue into the pleura, so they’re more strongly associated with pleural mesothelioma.
There is no doubt that asbestos exposure is a risk factor for developing lung cancer. Still, cigarette smoking remains the biggest risk factor. Asbestos exposure in non-smokers creates an increased risk for lung cancer, with the risk being about 10 times higher than without asbestos exposure. People who were exposed to asbestos and who also smoke have about 50 times the risk of lung cancer as non-smokers with no asbestos exposure.
What Are the Symptoms of Asbestos-Related Lung Cancer?
These symptoms are similar to those of many other respiratory diseases, including pneumonia, asthma and COPD (emphysema). Other types of cancer, such as mesothelioma or cancer that has spread from another part of the body may cause the same symptoms.
How Is Asbestos-Related Lung Cancer Diagnosed?
Types of Lung Cancer
Staging of Lung Cancer
The process of staging refers to determining how advanced a cancer is. As part of the process of diagnosis, doctors will also stage the cancer. For different types of cancer, the stage is described in different ways.
For NSCLC, a system of four stages is generally used, with higher numbers indicating more advanced disease.
How Is a Case of Lung Cancer Determined to Be Asbestos-Related?
Chrysotile asbestos does not tend to accumulate in lung tissue because the fibers can break apart, so significant levels of asbestos may not be found when a tissue sample is examined, even if a patient has had high levels of exposure to chrysotile asbestos. However, patients who have been exposed to amphibole asbestos will often have asbestos fibers found in their lung tissue because the longer fibers tend to embed into tissue and remain for a long time.
What Are the Treatment Options for Asbestos-Related Lung Cancer?
Lung cancer is far more common than mesothelioma. Mesothelioma patients often need to travel to a specific cancer center in order to access an expert on their disease, while lung cancer patients may find oncology experts who are familiar with their disease more readily. Still, many patients are treated at a cancer center in order to more easily access all of the health care that they need.