Mesothelioma

An aggressive cancer affecting the internal organs often really hard to diagnose!

A little History of the disease! In the late 18^th century, the tumors of the mesothelioma were first discovered. But it was analyzed and examined in detail in the middle of 20^th century.

What Actually Is Mesothelioma (me-zoe-thee-lee-OH-muh)? Mesothelioma (cancerous tumor) is a rare type of cancer which affects the mesothelium—the membranes which line the chest and abdominal cavities, and cover the lungs, heart and abdomen. This protective lining produces a lubricating fluid, which allows the organ to move against one another without friction as the body moves. Mesothelium cells are found in the lining of a number of vital internal organs of the body, like the stomach and heart. In other words within the body the cavities which surround the chest, abdomen and heart by a membrane of cells called the mesothelioma. The mesothelioma cells are usually present in the organs which are commonly related to organs in motion like muscular contraction and expansion of lungs, heart or stomach. When cancer penetrates this part of body, it can be very destructive.

It is very hard for doctors to make a correct diagnosis for the mesothelioma as it usually presents with indications that imitate other common bodily disorders. In other words prognosis is very poor.

Mesothelioma may occur in many different parts of the body because the body is composed of numerous mesothelium cells that divide constantly. Each year in United States about 2,000 new cases are diagnosed but its rate is increasing in other parts of the world. In between 1970 and 1980 a number of cases were recorded of this disease then it aggravated due to the more industrial exposure, military industry and Navy shipyards.

The mesothelium cells in chest are called pleura, in abdomen these called peritoneum and in cardiac cavity are called the pericardium.

Some very common types of Mesothelioma which are observed are further discussed below.

How many types of Mesothelioma according to area of the body? Mesothelioma is of three types according to area of the body:

•     Pleural mesothelioma
•    Peritoneal mesothelioma
•    Pericardial mesothelioma

 Pleural mesothelioma is the most common type of mesothelioma which starts from the lining of lungs also known as pleural or pleura membrane. About 70 – 80% cases are diagnosed with this type. The pleura consist of two layers, which provide protection and support for the chest cavity and lungs. Typically Pleural mesothelioma develops in one layer, but it can also spread to the other layer too. Furthermore when the cells of pleural becomes cancerous, they begin to split continuously, actually cutting down the capacity of lungs and in between layers of pleural it will buildup fluid. The symptoms of Pleural mesothelioma are usually constant dry or raspy cough, hemoptysis (coughing up blood), dysphagia (trouble in swallowing) , dyspnea (shortness of breath that occurs even when at rest), constant pain in the rib or chest area, or difficulty in breathing, growth of lumps under the skin on the chest, Night sweats or fever, loss of weight and Fatigue.

Peritoneal mesothelioma starts from the lining of the abdominal cavity. It is the rare type of mesothelioma.

About 10 - 20% cases are diagnosed with this type. In United States about 200-500 cases are being reported. In this type misdiagnosis is also very common due to imitative stomach discomfort and hernia. The peritoneum consists of two parts, the visceral and parietal peritoneum. The visceral layer makes the most of the outermost layer of intestinal tract and it also protects the internal organs. The parietal peritoneum covers the abdominal cavity. The symptoms of peritoneal mesothelioma are ascites (abnormal collection of fluid), swelling or pain in abdomen, loss of weight, obstruction of bowel, anemia (reduction of red blood cells), and fever.

Pericardial mesothelioma is the rarest type of mesothelioma starts from the lining of the heart (pericardium).It occurs 1 - 6 % of mesotheliomas. Only 200 cases are documented up till now worldwide. This cancer develops in the pericardium. The pericardium consists of two layers the outer layer is parietal layer (theca cordis or heart sac), and an inner layer is visceral layer (also known as the epicardium). The parietal layer covers the entire chest cavity while the visceral layer lines only the heart. The symptoms of pericardial mesothelioma are arrhythmia (irregular heartbeat), pain in chest, murmurs, cough, dyspnea (difficulty in breathing), Orthopnea (dyspnea which occurs while lying down), fatigue, night sweats and fever.

A very much uncommon type of mesothelioma is Testicular mesothelioma also called tunica vaginalis. It is so rare that about less than 100 cases are recorded until now. It starts from the lining of tunica vaginalis – it is a lining that protects and surrounds the reproductive organ inside the scrotum. Due to extremely rareness of Testicular mesothelioma there is no recognized symptoms related to Testicular mesothelioma yet. In few diagnosed cases this type of cancer is related with scrotal swelling and lumps on testicles. It is quite impossible to diagnose this type of mesothelioma until swelling or lumps appear.

How many types of Mesothelioma according to cell type of the tumor? There are mainly three types of mesothelioma found in terms of the cell type of the tumor:

• Epitheliod
• Sarcomatiod
• Mixed/biphasic

Epitheliod (Epithelial mesothelioma) 

It is the most common type, it occurs in about 50 - 70% cases. This cancer occurs in the epithelial cells within the lining surrounding the internal organs.

Sarcomatiod (Sarcomatous mesothelioma) 

 

This cancerous tumor occurs in the mesothelial lining or in the fibrous tissues. This type is found in 7 – 20% of cases.

Mixed/biphasic

This originates when a mix of both epithelial and sarcomatous involvement is found. About 20 – 35% cases, are found with mixed/biphasic mesothelioma.