The most critical form of mesothelioma is the malignant form. Known as malignant mesothelioma, the primary causal factor is asbestos infection. According to the US National Cancer Institute, “Malignant mesothelioma is a disease in which cancer (malignant) cells are found in the sac lining the chest (the pleura), the lining of the abdominal cavity (the peritoneum) or the lining around the heart (the pericardium).”

Mesothelioma can be classified into three types – pleural mesothelioma, peritoneal mesothelioma and pericardial mesothelioma. Pleural mesothelioma refers to a cancer of the lining of the lung (pleura), peritoneal mesothelioma refers to a cancer of the abdominal cavity (peritoneum) lining, and pericardial mesothelioma is a cancer that occurs in the lining that surrounds the heart (pericardium). The subtypes of mesothelioma are of three basic types, one very aggressive, one least aggressive, and one lying between the two extremes.

Malignant mesothelioma can be diagnosed through several imaging techniques. These imaging techniques enable physicians to assess mesothelioma. Once mesothelioma is suspected, patients are advised to undergo several tests, like X-ray, Computed Tomography (CT) scan, Magnetic Resonance Imaging (MRI) scans, and Positron Emission Tomography (PET) imaging. The physician may also like to undertake special mesothelioma tests like thoracoscopy, peritoneoscopy and biopsy.

Learning about the stage of mesothelioma is a critical factor that helps physicians to decide the treatment plan. If the cancer is confined to the pleura, mesothelioma is considered localized. If the cancer spreads beyond the pleura and to other parts of the body such as the lungs, abdominal cavity, lymph nodes and the chest wall, mesothelioma is considered to be in an advanced stage.

The oft used and the oldest system for determining the stages of mesothelioma is the Butchart System. The Butchart System is based on the extent of the primary tumor mass available in a patient. This system divides mesothelioma into four stages. The TNM system, a slightly advanced system over the Butchart System, determines staging through variables of tumor in mass and the spread, the lymph node involvement and metastasis. However, the latest system is known as the Brigham System, where staging is done as per the respectability and lymph node involvement. In spite of such modern techniques, a definitive diagnosis of mesothelioma still remains possible through fluid diagnosis and tissue biopsy.

Mesothelioma can either be malignant (cancerous) or benign (non-cancerous) in nature. Mesothelioma affects the mesothelium, hence mesothelioma. What is the mesothelium?

The mesothelium is a type of tissue lined with special cells referred to as mesothelial cells. The mesothelial cells typically line the abdominal cavity, heart cavity, chest cavity, and the outer surface of most internal organs. Each cavity has a specific name for the mesothelial covered cavity which is:

• Peritoneum: abdominal cavity
• Pleura: chest cavity
• Pericardium: heart cavity

The mesothelium has a specific purpose in the body. The mesothelium produces a lubricating fluid that allows easy movement of the organs. The pleural mesothelium for example, allows the lungs to move easily with each breath that is taken. Without this, breathing would be a difficult and possibly painful process.Many refer to malignant mesothelioma as simply, mesothelioma. There are three main types of malignant mesothelioma ranked from less likely to more commonly seen:

1. Sarcomatoid
2. Mixed/Biphasic
3. Epithelioid

Malignant mesothelioma more commonly begins in the chest cavity (pleural mesothelioma). Approximately 10-20% of the cases of malignant mesothelioma will begin in the abdominal cavity (peritoneal mesothelioma). Malignant mesothelioma rarely begins in the cavity surrounding the heart (pericardial mesothelioma).Malignant Mesothelioma Statistics:

Mesothelioma is a very rare cancer estimated to affect 2,000-3,000 newly diagnosed cases annually in the U.S. The United States reported an increased rate of mesothelioma from 1970 to 1990, which has currently stabilized and possibly decreased. However, European countries continue to see an increase in the rate of mesothelioma.

Mesothelioma is commonly seen in the ages 65 years and older but increases with age. Mesothelioma is 5 times more likely to affect men than women. Mesothelioma is more common in the Caucasian nationality than African American.

Mesothelioma is a very serious cancer. Symptoms commonly do not appear early which causes mesothelioma to be diagnosed at an advanced stage. For this reason, mesothelioma has a low survival rate that is about 1-2 years. However, cancer research is slowly changing this statistic. Learn more about what risk factors predispose you to mesothelioma.

Pleural effusion is an accumulation of fluid between the lining of the lung and the chest cavity. It is one of most common symptoms of mesothelioma and leads to shortness of breath. As the fluid collects in the lining of the lungs and chest, the pain and shortness of breath also increase. Dyspnea is shortness of breath which can be caused by a pleural effusion and/or by the presence of a tumor in the pleura or the lining of the lungs.

A buildup of fluid in the pleural can create a feeling of fullness and pressure, causing areas of pain in the chest cavity and sometimes in the lower back area. Chest pain occurs more often on the right side of the body, as mesothelioma affects the right lung 60% of the time. Only 5% patients suffer from mesothelioma in both lungs.

In some cases, a patient may also have chronic hoarseness, difficulty swallowing (dysphagia) and/or the coughing up of blood (hemoptysis). These are the rare symptoms of mesothelioma and seen in less than 1% mesothelioma patients. If the patient also suffers from swelling of the face or neck areas, it means that the cancer has spread beyond the mesothelium.

Peritoneal Mesothelioma

The other type of mesothelioma is peritoneal which attacks the lining of the stomach or the abdominal cavity. It can cause symptoms like:

Abdominal pain and swelling due to a buildup of fluid in the abdomen also known as ascites is one of the symptoms of peritoneal mesothelioma. If there is a tumor in the peritoneum membrane, it can put increasing pressure on the organs in the abdomen, leading to bowel obstruction and distention.

Pericardial Mesothelioma

The third type of mesothelioma is pericardial mesothelioma which attacks the lining of the chest cavity. It is not a common type of cancer. It can cause symptoms like:

Pericardial effusion may also occur in pericardial mesothelioma. It is the accumulation of liquid in the lining of the chest cavity which may cause difficulty in breathing and shortness of breath. The patient may also complain of irregular heartbeat which is caused due to liquid accumulation in the chest. Persistent cough along with blood may also occur. Pericardial mesothelioma can also lead to lung cancer.

Some of these symptoms can help you identify mesothelioma. Some patients show no symptoms of their mesothelioma which makes it more difficult to diagnose. The exact symptoms will often depend on the area where mesothelioma affects which will help you identify mesothelioma.