01. How Asbestos Causes Cancer
How Does Asbestos Cause Cancer?
Inhaling or swallowing asbestos fibers can cause cancer. Asbestos is a mineral made of microscopic fibers. Once the fibers enter the body, they cannot be broken down or removed. As a result, the fibers can cause irritation and inflammation. Over time, asbestos can cause genetic mutations and cancer.
Many asbestos diseases are latent diseases. In other words, it can take years for asbestos cancer symptoms to emerge. Mesothelioma and asbestos lung cancer patients often aren’t diagnosed until 10 – 50 years after their first exposure.
What Types of Asbestos Cause Cancer?
All six types of asbestos cause cancer. Asbestos types are classified as either serpentine or amphibole asbestos.
Chrysotile asbestos belongs to the serpentine family. It is also the most common type of asbestos. All other types of asbestos belong to the amphibole family. This group includes amosite, crocidolite, tremolite, actinolite and anthophyllite asbestos.
Some studies suggest exposure to amphibole fibers is more likely to cause asbestos cancer. However, more research is needed.
02. Asbestos Cancer Types
What Types of Cancer Are Caused by Asbestos?
According to the International Agency for Research on Cancer (IARC), cancers definitively caused by asbestos include:
- Asbestos is the only known cause of mesothelioma.
- Asbestos fibers can become lodged in organ linings (mesothelium).
- Mesothelioma cancer typically occurs within the lungs or the abdomen.
- Asbestos fibers can become lodged in the lung tissues.
- Asbestos lung cancer symptoms may take more than a decade to emerge.
- Smoking increases the risk of developing asbestos-related lung cancer.
- Asbestos can reach the ovaries by traveling through the reproductive system, bloodstream or lymphatic system.
- Studies continue to research the connection between asbestos-contaminated talcum powder and ovarian cancer.
- Asbestos fibers can become lodged in the tissues of the voice box when traveling to the lungs.
- Smoking, heavy alcohol use and exposure to other toxins can increase the risk of asbestos-related laryngeal cancer.
The IARC is part of the World Health Organization (WHO) and a leading organization in cancer research. It conducts, coordinates and publishes research regarding worldwide cancer causes and cancer occurrence.
Many studies may find a correlation between asbestos and other types of cancers, such as breast cancer, stomach cancer and colon cancer. However, the IARC has only asserted definitive causal relationships between asbestos and the above cancers. In other words, the agency’s studies have concluded asbestos is a cause of four types of cancer. Other research organizations have published studies that support the IARC’s findings.
Asbestos exposure can lead to the development of mesothelioma cancer. Mesothelioma is a rare cancer that develops in organ linings.
After an individual swallows or inhales asbestos fibers, the fibers can become embedded in their organ linings. Once embedded, the microscopic asbestos fibers can cause inflammation, irritation and mutation. Mutation of the mesothelial cells can lead to the development of mesothelioma.
The development of mesothelioma cancer is most common in the pleura (lung linings). However, mesothelioma may also develop in the abdomen, heart or testes. The location of the affected tissues determines mesothelioma type.
Asbestos and Mesothelioma Quick Facts
- Asbestos is the only definitive cause of mesothelioma.
- Any amount of asbestos exposure can cause mesothelioma.
- The term “asbestos cancer” most commonly refers to mesothelioma.
- There were 3,109 new cases of mesothelioma reported in 2017.*
*Data for the United States, provided by the Centers for Disease Control and Prevention (CDC)
Asbestos exposure can also lead to lung cancer. Asbestos lung cancer develops within the lungs after asbestos fibers are inhaled and become lodged in the lung tissue. The fibers then can cause irritation, genetic mutation and the growth of malignant cells.
The development of asbestos-related lung cancer can take years. As a result, asbestos victims may not recognize symptoms for more than a decade after initial exposure.
Research has found long-term asbestos exposure increases the likelihood of developing asbestos-related lung cancer. However, there are several other risk factors, such as smoking.
Lung Cancer and Asbestos Quick Facts
- According to the American Cancer Society, asbestos lung cancer typically emerges 15 years after exposure.
- Higher levels of exposure lead to a higher risk of lung cancer.
- Many studies focus on the relationship between occupational exposure and lung cancer.
- There will be an estimated 135,720 deaths from lung and bronchus cancer in 2020.* Research has previously indicated asbestos causes around 4% of lung cancer cases.
*Estimates for the United States, provided by the National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results Program (SEER)
Asbestos exposure can lead to ovarian cancer. Asbestos-related ovarian cancer is caused when asbestos fibers travel through the body to the ovaries. There are two main ways asbestos can reach the ovaries:
- Applying asbestos-contaminated products (such as talcum powder) to the genitals. Fibers then travel through the reproductive system.
- Inhaling or swallowing asbestos. Fibers then travel through the bloodstream or the lymphatic system to the ovaries.
The IARC recognized asbestos as a proven cause of ovarian cancer in 2009. New studies continue to support this finding.
Ovarian Cancer and Asbestos Quick Facts
- Some studies note an increased risk of ovarian cancer with regular talcum powder use. Talcum powder can be particularly dangerous if contaminated with asbestos.
- Cases of ovarian cancer have been linked to secondary exposure from men who held high-risk asbestos occupations.
- Medical history, old age and hormonal treatments may increase a woman’s risk of ovarian cancer from asbestos.
- There will be an estimated 13,940 deaths from ovarian cancer in 2020.* Research is limited on what percentage of cases is directly linked to asbestos.
*Estimates for the United States, provided by the NCI SEER Program
Asbestos exposure can lead to laryngeal cancer (cancer of the voice box). Asbestos-related laryngeal cancer is caused by inhaling asbestos. Fibers must travel through the larynx before reaching the lungs. As a result, fibers can embed in the tissues of the voice box. This can then lead to the development of malignant cells.
The link between laryngeal cancer and asbestos was previously unknown. However, a 2006 study by the National Institutes of Health (NIH) confirmed the relationship. Many additional studies have since supported asbestos as a cause.
Laryngeal Cancer and Asbestos Quick Facts
- Studies have found a correlation between levels of asbestos exposure and laryngeal cancer mortality rates.
- Smoking and excessive alcohol use may increase the risk of asbestos-related laryngeal cancer.
- Exposure to other carcinogens, such as silica dust, may lead to an increased risk of asbestos-related laryngeal cancer.
- There will be an estimated 3,750 laryngeal cancer deaths in 2020.* The percentage of cases directly linked to asbestos is currently unknown.
*Estimates for the United States, provided by the NCI SEER Program
Other Asbestos-Related Diseases
Asbestos exposure can cause other serious conditions, such as asbestosis. Some studies have found possible correlations between asbestos and other cancers, including:
- Kidney cancer
- Breast cancer
- Esophageal cancer
- Prostate cancer
The IARC recognizes positive associations between asbestos and the following cancers:
- Rectal cancer
- Pharyngeal cancer
- Stomach cancer
- Colon cancer
Non-Malignant Asbestos Illnesses
Non-cancerous conditions caused by asbestos exposure may vary in severity.
- Asbestosis: Chronic lung disease from scarring of lung tissue
- Chronic obstructive pulmonary disease (COPD): Chronic inflammatory lung disease interfering with air movement to the lungs
- Pleural plaques: Areas of benign thickening in the lung linings
- Pleural thickening: Thickening of the lung lining with scar tissue
- Pleural effusion: Buildup of fluid around the lungs
- Peritoneal effusion: Buildup of fluid around the abdomen
- Pericardial effusion: Buildup of fluid around the heart
- Rounded atelectasis: Folding of lung tissue
Patients may be diagnosed only with a benign asbestos disease. However, a benign condition could also be associated with a malignant condition. For example, pleural effusion is a symptom of pleural mesothelioma.
03. Risk Factors
Asbestos Cancer Risk Factors
Studies have found several factors that increase the risk of developing asbestos cancer after exposure. These risk factors include:
- Alcohol use
- Poor health
- Poor diet
- Other medical conditions
People can come in contact with asbestos through using products that contain asbestos, their occupational tasks or close contact with another person who was exposed to asbestos. Although no level of exposure is safe, long-term exposure increases the risk of asbestos cancer.
Individuals who know they have been exposed to asbestos should inform their doctor as soon as possible. Frequent monitoring can help increase the likelihood of early detection. If asbestos cancers are detected in the early stages, patients may be able to improve their prognosis with aggressive treatments.
Resources for Mesothelioma Patients
How Is Asbestos Cancer Diagnosed?
Asbestos cancer is typically diagnosed by:
- Examining the patient’s medical history
- Analyzing symptoms
- Conducting blood tests to rule out minor conditions and identify potential biomarkers
- Performing imaging scans, such as X-rays or CT scans, to locate abnormalities
- Conducting a biopsy to determine if affected tissues are benign or malignant
Patients should seek medical care as soon as they recognize symptoms of cancer related to asbestos. They should also disclose any known history of asbestos exposure.
Asbestos Cancer Symptoms
Common asbestos cancer symptoms include:
- Chest pain
- Abdominal pain
- Difficulty breathing
- Difficulty swallowing
or sexual changes
Asbestos cancer symptoms may vary based on the type of cancer.
05. Treating Asbestos Cancer
Asbestos Cancer Treatment
Asbestos-related cancers are typically treated with surgery, chemotherapy and radiation. Experimental treatments may also be an option for patients. Treatment plans will vary on a case-by-case basis. Personalized treatment plans will consider multiple factors, including cancer type, stage, overall health, age and other patient characteristics.
Patients should seek care from a specialist to ensure they receive an accurate diagnosis and proper treatment. For example, mesothelioma specialists have a deep understanding of what treatment options work best for different types of mesothelioma. An experienced specialist will also know what clinical trials may be available.