Mesothelioma is a cancer caused by asbestos exposure
Mesothelioma is a type of cancer that develops in the thin layer of tissue covering most internal organs. It forms when someone breathes in or swallows asbestos fibers — a mineral that was widely used in building materials, insulation, and industrial products for decades. The fibers get stuck in the tissue lining the lungs, heart, or abdomen and cause inflammation and cell damage that can lead to cancer years or even decades later.
Most people with mesothelioma were exposed to asbestos at work, often without knowing it was dangerous. Construction workers, military veterans, factory workers, and people who handled old insulation or brake pads face higher risk. Family members of workers can also be exposed if asbestos dust was brought home on clothing or equipment.
The disease is serious because it is usually found at a late stage, when the cancer has already spread. There is no cure, but treatment can slow the disease and manage symptoms.
Key Takeaways
- Mesothelioma develops after asbestos fibers lodge in the tissue lining the lungs, heart, or abdomen and cause cancer over time.
- Symptoms like chest pain, persistent cough, or abdominal swelling often do not appear until 20 to 50 years after asbestos exposure.
- Doctors diagnose mesothelioma using imaging tests like CT scans and X-rays, followed by a biopsy to confirm cancer cells.
- Treatment options include surgery, chemotherapy, and radiation, often used together to manage the disease.
- If you were exposed to asbestos at work or in the military, tell your doctor so they can monitor you for early signs.
How asbestos causes mesothelioma
Asbestos is made of tiny fibers that are invisible to the naked eye. When asbestos-containing materials break down or are disturbed — during demolition, renovation, or manufacturing — these fibers become airborne. A person can inhale them without realizing it.
Once inside the body, the fibers travel to the lining of the lungs (called the pleura), the lining around the heart (the pericardium), or the lining of the abdomen (the peritoneum). The body cannot break down or remove asbestos fibers, so they stay there permanently. Over years or decades, they irritate the tissue, cause scarring, and trigger genetic changes that lead to cancer.
The long delay between exposure and disease — called the latency period — is one reason mesothelioma is so difficult to catch early. A person may have been exposed 30 or 40 years ago and have no idea they are at risk.
Three types of mesothelioma based on location
Pleural mesothelioma is the most common type, accounting for about 75 percent of cases. It forms in the lining around the lungs and causes chest pain, coughing, and shortness of breath.
Peritoneal mesothelioma develops in the abdominal lining and is less common. It causes abdominal pain, swelling, and digestive problems. People with this type may have swallowed asbestos fibers or had fibers travel through the body to the abdomen.
Pericardial mesothelioma is rare and forms in the lining around the heart. It can cause chest pain, irregular heartbeat, and difficulty breathing. This type is the hardest to diagnose because symptoms overlap with heart disease.
Symptoms and when they appear
Early mesothelioma often causes no symptoms at all. When symptoms do develop, they are usually vague and similar to other common conditions, which delays diagnosis.
For pleural mesothelioma, watch for a persistent cough that lasts more than a few weeks, chest pain that worsens when breathing or coughing, shortness of breath, and fluid buildup around the lungs. Some people develop a hoarse voice or have trouble swallowing.
Peritoneal mesothelioma may cause abdominal pain or swelling, nausea, vomiting, constipation, or weight loss. Pericardial mesothelioma can cause chest pain, heart palpitations, or persistent fatigue.
Because these symptoms can point to many other conditions — pneumonia, bronchitis, heart disease, or irritable bowel syndrome — people often see multiple doctors before mesothelioma is suspected. If you have a history of asbestos exposure and develop any of these symptoms, mention the exposure history to your doctor.
How doctors diagnose mesothelioma
Diagnosis starts with your medical history. Your doctor will ask about your work, military service, and any known asbestos exposure. They will listen to your lungs with a stethoscope and may order imaging tests.
A chest X-ray or CT scan (computed tomography) can show thickening of the pleura, fluid around the lungs, or masses in the abdomen. These images help narrow down the problem but cannot confirm cancer on their own.
To confirm mesothelioma, your doctor will take a tissue sample called a biopsy. For pleural mesothelioma, this may involve a needle biopsy (inserting a thin needle into the chest to collect tissue) or a thoracoscopy (a small camera inserted through the chest wall to view and sample tissue). For peritoneal mesothelioma, the doctor may perform a laparoscopy (a similar procedure in the abdomen).
A pathologist examines the tissue under a microscope to look for mesothelioma cells. They may also run special stains or genetic tests to confirm the diagnosis and determine the cell type, which helps guide treatment.
Staging and prognosis
Once mesothelioma is confirmed, doctors determine the stage — how far the cancer has spread. Staging helps predict how the disease will progress and guides treatment decisions.
Early stages (1 and 2) mean the cancer is localized to the tissue lining and may not have spread to lymph nodes or distant organs. Later stages (3 and 4) indicate spread to nearby tissues, lymph nodes, or other parts of the body. Most people are diagnosed at stage 3 or 4 because symptoms appear late.
Prognosis depends on the stage at diagnosis, the cell type, the person's age and overall health, and how well they respond to treatment. Median survival — the point at which half of patients have lived longer and half have not — ranges from about one to two years for advanced disease, though some people live longer with aggressive treatment.
Treatment options
Treatment usually combines surgery, chemotherapy, and sometimes radiation. The goal is to remove as much cancer as possible and slow the disease's progression.
Surgery may involve removing the affected tissue lining (pleurectomy for the lungs, peritonectomy for the abdomen) or, in some cases, removing the entire lung. Surgery is most effective when the cancer is caught early.
Chemotherapy uses drugs to kill cancer cells throughout the body. A common combination for mesothelioma is pemetrexed and cisplatin. Chemotherapy can be given before surgery to shrink tumors or after surgery to destroy remaining cells.
Radiation therapy uses high-energy beams to target cancer cells. It is sometimes used after surgery or combined with chemotherapy.
Newer treatments, including immunotherapy (which helps the immune system fight cancer) and clinical trials, may be options depending on the stage and type of mesothelioma. Your doctor will discuss which treatments are appropriate for your situation.
Frequently Asked Questions
How long after asbestos exposure does mesothelioma develop?
Mesothelioma typically develops 20 to 50 years after exposure, though cases have appeared as early as 10 years or as late as 70 years after exposure. This long latency period means people exposed decades ago may only now be developing symptoms. If you know you were exposed to asbestos, inform your doctor so they can monitor you.
Can mesothelioma be cured?
There is no cure for mesothelioma, but treatment can extend survival and manage symptoms. Surgery combined with chemotherapy offers the best outcomes, particularly when the cancer is caught early. Some people live several years with aggressive treatment, while others may live only months. Your doctor can discuss realistic expectations based on your diagnosis.
Is mesothelioma hereditary?
Mesothelioma itself is not inherited, but the risk of exposure may run in families if multiple family members worked in high-risk jobs like construction or military service. If a family member has mesothelioma, it does not mean you will develop it unless you were also exposed to asbestos.
What should I do if I think I was exposed to asbestos?
Tell your doctor about the exposure and when it occurred. Your doctor may recommend periodic imaging tests or monitoring, especially if you develop respiratory symptoms. There is no treatment to remove asbestos fibers from the body, but early detection of mesothelioma improves treatment options.
Can family members get mesothelioma from someone who has it?
Mesothelioma is not contagious and cannot spread from person to person. However, family members can develop mesothelioma if they were exposed to asbestos fibers brought home on a worker's clothing or equipment. If someone in your household worked with asbestos, wash their work clothes separately and avoid shaking out contaminated materials.