Mesothelioma

Mesothelioma is an aggressive cancer of the tissues that line the mesothelium, the protective membrane that covers the lungs, chest walls, heart, and abdomen. Most cases of this cancer occur due to asbestos exposure—a mineral found in several construction and industrial materials and household products. Though any contact with asbestos increases the risk of this cancer, mesothelioma is a rare type.

The symptoms of mesothelioma depend on the severity and the part of the body affected. Unfortunately, most people with mesothelioma receive their diagnosis in later stages, which can make treatment challenging. Still, there are many treatment options available that can improve the outlook for this condition.

Types

There are two ways healthcare providers categorize mesothelioma: by location and tumor type. Mesothelioma can show in the following parts of your body:

• Pleural: The lining of the lungs
• Peritoneal: Abdominal tissues
• Pericardial: The lining of the heart
• Tunica vaginalis testis: In the tissues of the vagina or testes

There are three types of mesothelioma tumors, which are broken down based on their cellular composition. These include:

• Epithelioid mesothelioma: Accounting for 80% of cases, epithelioid mesothelioma affects the epithelial cells, which make up the outer layer of the inner lining of your organs, body cavities, and blood vessels. This type often emerges first in the lungs (pleural mesothelioma) and is the most treatable.
• Sarcomatoid mesothelioma: A mixture of the two major cancer cell types: carcinoma and sarcoma. This type causes distinctive spindle-shaped cells and makes up about 10% of all mesothelioma cases. It's the rarest of the three types but the most aggressive and rapid.
• Mixed mesothelioma: Also known as biphasic mesothelioma, this cancer occurs when you have both epithelioid and sarcomatoid types.

Mesothelioma Symptoms 

Mesothelioma primarily affects the lungs and can spread to the abdominal wall, heart, or other organs. Symptoms depend on the exact part of the body that is affected.

Systemic Symptoms

Systemic symptoms are symptoms that affect the whole body. All types of mesothelioma may cause:

• Fever
• Sweating
• Fatigue
• Lethargy
• Blood clots, which can also cause swelling in the limbs and chest pain
• Unexplained weight loss
  
• Loss of appetite

Respiratory Symptoms

Most cases of mesothelioma are pleural, or affect the lungs. As a result, you may experience:

• Lower back pain
• Pain in the side of the chest
• Shortness of breath
  
• Difficulty swallowing food
• Hoarse voice
• Chronic cough
• Facial swelling
• Swollen arms
  

Abdominal Symptoms

When the cancer spreads to the walls that line the inside of the abdomen (known as peritoneal mesothelioma) symptoms may include:

• Abdominal pain
• Swelling or fluid buildup
• Nausea and vomiting
• Constipation

Cardiac Symptoms

Pericardial mesothelioma affects the tissues that line the heart (which are a part of your cardiovascular system). If you develop this type of cancer, you may experience the following:

• Chest pain (known as angina)
• Irregular or racing heartbeat
• Heart murmur

Causes 

Mesothelioma occurs when cancer cells form in the mesothelial tissue that lines organs or cavities in your body. The DNA (genetic code) in these cells is abnormal. As a result, they divide more rapidly than healthy cells and can spread to other parts of the body quickly.

Over 80% of mesothelioma cases are the result of asbestos exposure—a harmful building and industrial material and ingredient in certain products. When inhaled or ingested, asbestos causes damage and inflammation in your cells, which can make them cancerous. This is a delayed process. Mesothelioma typically develops anywhere from 20-40 years after exposure.

Risk Factors

Exposure to asbestos, through construction, industrial work, or handling certain products or building materials, is the primary risk factor for mesothelioma. Other factors also play a role, including:

• Older age, usually above 45
• Radiation therapy
• Being assigned male at birth
• Genetic mutations which can increase your risk of mesothelioma
• Smoking

Diagnosis

If you are experiencing symptoms of mesothelioma or may have been exposed to asbestos, it's important to seek care from a healthcare provider for proper diagnosis. Your provider will first ask about your medical history and perform a physical exam. They'll also try to rule out other potential causes of your symptoms, such as other types of lung cancer, lung infections, medication side effects, or lung fibrosis.

Several diagnostic tests can also help healthcare providers detect mesothelioma, such as:

• Fluid test: Tests samples of fluid from the chest (thoracentesis), abdomen (paracentesis), or surrounding the heart (pericardiocentesis) for signs of cancer
• Blood test: Checks for elevated levels of fibulin-3 and soluble mesothelin-related peptides (SMRPs) in the blood, which may be signs of mesothelioma
• Biopsy: Uses a syringe or surgery to collect a sample of tumor tissue to check for the presence of cancer cells
• Chest X-ray: Detects thickening in the lung walls, calcium deposits, fluid buildup, or other signs of lung damage
• Computed tomography (CT) scan: Creates three-dimensional representations of your tissues to locate tumors, see if the cancer has spread, or evaluate further for treatment
• Magnetic resonance imaging (MRI) scan: Makes detailed images of soft tissues to locate and evaluate any tumors

Stages of Mesothelioma

After evaluating your scans and biopsies, your healthcare provider will stage the disease if you test positive for mesothelioma. The stages are as follows:

• Stage 1: Tumor in the pleural tissue of the lungs, diaphragm, or other tissues but no signs of spread to lymph nodes or other parts of your body
• Stage 2: Tumor in the pleural tissue of lungs, diaphragm, or other tissue, which has started to spread to the lymph nodes but no signs of cancer cells in other parts of your body
• Stage 3: Tumor has started to spread locally, moving into the abdominal walls, pericardium, chest wall, or lymph nodes
• Stage 4: Tumor has spread locally and to distant parts of the body

Mesothelioma Treatment  

Your exact treatment plan for mesothelioma will depend on the severity of your condition and the symptoms you're experiencing. Current options include surgeries to remove tumors, chemotherapy or radiation therapy to stop the spread of cancer cells, and medications or other procedures to manage symptoms.

Surgery

Several surgeries can remove mesothelioma tumors. Surgeons may remove them from the pleura and other lung tissues with a pleurectomy/decortication (P/D). For more serious cases, an extrapleural pneumonectomy (EPP) can help remove the damaged lung.

Chemotherapy

Chemotherapy involves repeat doses of medications that you take via an intravenous (IV) injection to prevent cancer from growing or spreading. For mesothelioma, common chemotherapy drugs include a combination of Alimta (pemetrexed) and Platinol (cisplatin), which you can take every 21 days as needed or as much as you can tolerate.

Radiation Therapy

Radiation therapy—directing radio waves (often X-rays) to the tumors—is not as effective as other treatments for mesothelioma on its own. However, oncologists may use this treatment alongside surgery to help ease pain associated with tumor growth.

Immunotherapy

A relatively newer approach, immunotherapy involves taking specific medications that trigger the immune system to attack cancer cells. For mesothelioma, combinations of Opdivo (nivolumab) and Yervoy (ipilimumab) may be part of the treatment plan if you're between stage 2 and stage 4 mesothelioma.

Palliative Procedures

Palliative procedures aim to ease the pain and discomfort associated with fluid buildup in the lung cavities. These treatments include:

• Pleurodesis: Surgeons make a small cut in the chest and place a tube to drain fluid buildup in the chest cavity and reduce symptoms.
• Shunt placement: Shunts are small, pump-like devices that move fluid from one body cavity to another via small holes. This eases pain and pressure in the abdomen or other body cavities.
• Catheter placement: Excess fluid buildup runs out of a tube (or catheter) via a small incision in the body to limit pain and pressure.

Pain Management

Alongside other therapies, your provider may prescribe analgesic medications to relieve severe pain. These medications may include opioids like Oxycontin (oxycodone). Keep in mind: opioids have serious side effects and can become addictive, so they’re only a short-term solution.

How To Prevent Mesothelioma

The most critical way to prevent mesothelioma is limiting or completely avoiding asbestos exposure. Until 1978, asbestos was often used for insulation and as a fire retardant in construction. Asbestos was also an ingredient in widely available building materials like shingles, siding, roofing, or flooring tiles until 1989.

If you work in construction or are at risk of asbestos exposure, it’s critical to wear a mask and follow other safety precautions to protect yourself. Consider having an expert test for asbestos in the air if your home was built before 1979. Since early detection radically improves outcomes, it can also help talk to your healthcare provider about preventative screening.    

Related Conditions

Unfortunately, mesothelioma raises the risk of developing several other conditions. Some conditions or complications can also result from chemotherapy and surgery. Related conditions include:

• Chronic obstructive pulmonary disease (COPD): Affects your breathing ability and blocks airflow
• Coronary artery disease (CAD): Heart disease that causes damage to your heart's blood vessels
• Hypertension: High blood pressure
• Diabetes: Often occurs due to side effects of chemotherapy or surgery, making it more difficult for your body to properly use insulin
  
• Infection: Can develop at the site of surgery, especially if not cleaned properly
• Organ failure: May disrupt or stop the functioning of your kidneys, lungs, or heart

Living With Mesothelioma

Mesothelioma is an aggressive and severe type of cancer. Unfortunately, this condition is typically detected at a later stage, making treatment difficult. Without treatment, the life expectancy of mesothelioma is only four to six months. With treatment, people with this condition may live on average 18 months longer. However, some people continue living after five or more years.

The prognosis (outlook) improves with early detection. If you think you may have been exposed to asbestos or are experiencing symptoms, it's essential to get tested as soon as possible. Fortunately, researchers are developing promising new therapies, such as those targeting certain genes or stimulating immune responses, which may help improve outcomes.

Living with cancer—or caring for someone with it—can take a severe emotional toll, often leading to depression or anxiety. To help you better manage the emotional effects of mesothelioma, consider the following strategies:

• Relying on your loved ones for support
• Meeting with a mental health professional for therapy and coping strategies
• Joining a support group for other people with the condition, or loved ones that serve as caregivers for people with mesothelioma
• Taking part in clinical trials for new treatments
• Making your home a safe and comfortable environment
• Finding time for joy when you can, whether that's watching a funny show, engaging in hobbies you like, or spending time with people you love