What Is Malignant Mesothelioma?

Malignant mesothelioma is a disease in which malignant (cancer) cells are found in the mesothelium, which is a thin layer of tissue that covers most organs in the body. Mesothelioma most commonly affects the pleura (the thin layer of tissue that lines the chest cavity and covers the lungs) or the peritoneum (the thin layer of tissue that lines the abdomen and covers most of the organs in the abdomen). This article discusses malignant mesothelioma of the pleura.

What Are the Risk Factors?

Being exposed to asbestos can affect the risk of developing malignant mesothelioma. Many people with malignant mesothelioma have worked or lived in places where they inhaled or swallowed asbestos. After being exposed to asbestos, it usually takes a long time for malignant mesothelioma to occur.

Other risk factors for malignant mesothelioma include the following:

• Living with a person who works near asbestos.
• Being exposed to a certain virus.
  
  

Mesothelioma Research: An Introduction

Doctors and scientists all over the country are conducting mesothelioma research. These studies are designed to answer important questions and to determine whether new approaches are safe and effective. Research on mesothelioma already has led to many advances, and researchers continue to search for more effective methods for dealing with the condition. But controlling mesothelioma remains a challenge. Research scientists continue to search for more effective ways to treat this disease.

Current Areas of Research

In trials with people who have mesothelioma, doctors are studying new drugs, new combinations of chemotherapy, and combinations of chemotherapy and radiation therapy before and after surgery.

Biological therapy is also under investigation. Sometimes referred to as "biologic therapy," this is a treatment that uses the person's immune system to fight cancer. Substances made by the body or made in a laboratory are used to boost, direct, or restore the body's natural defenses against cancer. This type of cancer treatment is also called biotherapy or immunotherapy.

Asbestos Exposure and Symptoms of Mesothelioma

Up to 90 percent of malignant mesothelioma cases are related toasbestos exposure. The risk for developingmesothelioma in those with heavy asbestos exposure is 7 to 10 percent. However, symptoms may not appear until 30 to 50 years after exposure to asbestos.

 

Mesothelioma Symptoms: Final Thoughts

The possible symptoms of mesothelioma described in this article are not sure signs of the disease. Other more common, less serious conditions can cause similar symptoms. If you are experiencing any possible mesothelioma symptoms, visit your healthcare provider so that the problem can be diagnosed and treated.

Mesothelioma Signs and Symptoms: An Overview

Mesothelioma is a benign (noncancerous) or malignant (cancerous) tumor that begins within the mesothelium, a protective lining surrounding most of the organs in the body. Most mesotheliomas begin within the pleura (the membrane that surrounds the lungs and lines the wall of the chest cavity) or the peritoneum (the mesothelial tissue that covers most of the organs in the abdominal cavity). Mesothelioma symptoms will vary, depending on where the tumor is located.

Pleural Symptoms of Mesothelioma

Pleural mesothelioma symptoms are usually due to an accumulation of fluid in the pleura. These symptoms often include:

• Shortness of breath
• Pain in the chest or under the ribcage.

Mesothelioma Diagnosis (Cont.)

Biopsy

A biopsy is needed to confirm amesothelioma diagnosis. In a biopsy, a surgeon or a medical oncologist (a doctor who specializes in diagnosing and treating cancer) removes a sample of tissue for examination under a microscope by a pathologist. A biopsy may be performed in different ways, depending on where the abnormal area is located.

Thoracoscopy

If the cancer is in the chest, the doctor may perform a thoracoscopy. In this procedure, the doctor makes a small cut through the chest wall and puts a thin, lighted tube called a thoracoscope into the chest between two ribs. Thoracoscopy allows the doctor to look inside the chest and obtain tissue samples.

Peritoneoscopy

If the cancer is in the abdomen, the doctor may perform a peritoneoscopy. To obtain tissue for examination, the doctor makes a small opening in the abdomen and inserts a special instrument called a peritoneoscope into the abdominal cavity.

Mesothelioma Diagnosis: An Overview

Mesothelioma Diagnosis: An Overview

Making a mesothelioma diagnosis is often difficult because mesothelioma symptoms are similar to those of a number of other conditions.

In order to make a diagnosis of mesothelioma, the healthcare provider will begin with a review of the patient's medical history, including any history of asbestos exposure. He or she will then perform a complete physical examination to look for signs or symptoms of mesothelioma. The doctor may also order some preliminary tests to rule out other, more common conditions. These tests can include x-rays of the chest or abdomen and lung function tests.

Treatment Options

Treatment options for malignant pleural mesothelioma may include:

• Surgery .
• Radiation therapy .
• Chemotherapy .

Key Facts on Malignant Pleural Mesothelioma

The following is a summary of key points to keep in mind about malignant pleural mesothelioma:

• Malignant pleural mesothelioma is a disease in which malignant (cancerous) cells form in the lining of the chest 
• Being exposed to asbestos can affect the risk of developing this disease .
• Possible signs include shortness of breath and pain under the ribcage .
• Tests that examine the inside of the chest are used to find and diagnose malignant pleural mesothelioma .
• Certain factors affect prognosis (chance of recovery) and treatment options .

How Is It Diagnosed?

Sometimes it is hard to tell the difference between malignant pleural mesotheliomaand lung cancer, so tests are performed to examine the inside of the chest to accurately diagnose the condition.

The following tests and procedures may be used:

• Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the person's health habits, exposure to asbestos, past illnesses, and treatments will also be taken.
• Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
• Complete blood count (CBC): A procedure in which a sample of blood is drawn and checked for the following:

• The number of red blood cells, white blood cells, and platelets
• The amount of hemoglobin (the protein that carries oxygen) in the red blood cells
• The portion of the blood sample made up of red blood cells.

• Sedimentation rate: A procedure in which a sample of blood is drawn and checked for the rate at which the red blood cells settle to the bottom of the test tube.
• Biopsy: The removal of cells or tissues from the pleura so they can be viewed under a microscope by a pathologist to check for signs of malignant pleural mesothelioma. Procedures used to collect the cells or tissues include the following:

• Fine-needle aspiration biopsy: The removal of part of a lump, suspicious tissue, or fluid, using a thin needle. This procedure is also called a needle biopsy.

•  Thoracoscopy: An incision (cut) is made between two ribs, and a thoracoscope (a thin, lighted tube) is inserted into the chest.

• Peritoneoscopy: An incision is made in the abdominal wall and a peritoneoscope (a thin, lighted tube) is inserted into the abdomen.

• Laparotomy: An incision is made in the wall of the abdomen (stomach) to check the inside of the abdomen for signs of disease.

• Thoracotomy: An incision is made between two ribs to check inside the chest for signs of disease.

Symptoms of Malignant Pleural Mesothelioma

Malignant pleural
 mesothelioma symptoms usually result from an accumulation of fluid in the pleura. These symptoms often consist of:

*Shortness of breath
*Pain in the chest or under the ribcage.

Keep in mind that other more common, less serious conditions can cause similar symptoms. Therefore, if you are experiencing any possible symptoms, visit your healthcare provider so that the problem can be properly diagnosed and treated.

What Is Malignant Pleural Mesothelioma?

Mesothelioma is a benign (noncancerous) or malignant (cancerous) tumor affecting the mesothelium, which is a type of protective sac that covers internal organs. Most cases begin in the pleura (lining around the lungs) or peritoneum (the lining around the abdomen).

 

Malignant pleural mesothelioma is a type of mesothelioma in which cancer cells begin to grow in the pleura. Most people who develop this condition have worked on jobs where they inhaled asbestos particles.

 

Statistics on Mesothelioma

Although reported incidence rates have increased in the past 20 years, mesothelioma is still a relatively rare cancer. About 2,000 new cases of mesothelioma are diagnosed in the United States each year. Mesothelioma occurs more often in men than in women and risk increases with age, but mesothelioma can appear in either men or women at any age.

How Is It Treated?

Treatment for mesothelioma depends on:

 

• The location of the cancer
• The stage of the disease
• The patient's age and general health.
   

Standard mesothelioma treatment options include:

 

• Surgery
• Radiation therapy
• Chemotherapy.
   

Sometimes, all three treatment methods are combined.

Mesothelioma and Asbestos

Asbestos is the name of a group of minerals that occur naturally as masses of strong, flexible fibers that can be separated into thin threads and woven. Asbestos has been mined and used commercially since the late 1800s; its use greatly increased during World War II. Asbestos has been widely used in many industrial products, including cement, brake linings, roof shingles, flooring products, textiles, and insulation. Since the early 1940s, millions of American workers have been exposed to asbestos dust.

If tiny asbestos particles float in the air, especially during the manufacturing process, they may be inhaled or swallowed and can cause serious health problems. In addition to mesothelioma, exposure to asbestos increases the risk of lung cancer, asbestosis (a noncancerous, chronic lung ailment), and other cancers, such as those of the larynx and kidney.

Initially, the risks associated with asbestos exposure were unknown. However, an increased risk of developing mesothelioma was later found among:

*Shipyard workers

*People who work in asbestos mines and mills

*Producers of asbestos products

*Workers in the heating and construction industries

*Other tradespeople.

Risk Factors for Mesothelioma

Working with asbestos is the major risk factor for mesothelioma. A history of asbestos exposure at work is reported in about 70 to 80 percent of all cases. However, mesothelioma has been reported in some individuals without any known exposure to asbestos.

There is some evidence that family members and others living with asbestos workers have an increased risk of developing mesothelioma, and possibly other asbestos-related diseases. This risk may be the result of exposure to asbestos dust brought home on the clothing and hair of asbestos workers. To reduce the chance of exposing family members to asbestos fibers, asbestos workers are usually required to shower and change their clothing before leaving the workplace.

Understanding the Mesothelium

The mesothelium is a membrane that covers and protects most of the internal organs of the body. It is composed of two layers of cells: one layer immediately surrounds the organ; the other forms a sac around it. The mesothelium produces a lubricating fluid that is released between these layers, allowing moving organs (such as the beating heart and the expanding and contracting lungs) to glide easily against adjacent structures.



The mesothelium has different names, depending on its location in the body. The peritoneum is the mesothelial tissue that covers most of the organs in the abdominal cavity. The pleura is the membrane that surrounds the lungs and lines the wall of the chest cavity, while the pericardium covers and protects the heart. The mesothelial tissue surrounding the male internal reproductive organs is called the tunica vaginalis testis, and the tunica serosa uteri covers the internal reproductive organs in women.

What Is Mesothelioma?

Mesothelioma is a rare form of cancer affecting the mesothelium, which is a membrane that covers and protects most of the internal organs of the body. In most cases, it begins in the pleura (the lining around the lungs) or peritoneum (the lining around the abdomen). The cancer is typically caused by asbestos exposure. A history of asbestos exposure at work is reported in about 70 to 80 percent of all cases of the disease. Standard treatment options include surgery, chemotherapy, and radiation therapy.