What is Mesothelioma?
Mesothelioma is a rare, aggressive form of cancer that attacks the tissue lining of internal organs. This protective tissue lining is known as the mesothelium. While the main cause of various cancers is vaguely understood, this form of cancer is a man-caused cancer which is directly associated to a person being exposed to asbestos. Once tiny asbestos fibers have entered the body via esophageal or tracheal pathways, they will become lodged into the protective tissue lining mentioned above. This lodging disrupts natural cell development, which promotes the growth of abnormal cells. The uncontrollable growth of cells is the general cause cancer.
The mesothelium consists of two layers:
- The inner layer of the mesothelium wraps directly around major organs like the lungs, abdomen, and heart. This is the first layer of protection.
- The outer mesothelium layer forms a sac that surrounds the inner layer; mesothelioma grows in between or on these two linings.
There are three known and medically accepted types of mesothelioma with the probability of there being a fourth type. The reason for the “probability” is because it is so rare that there isn’t enough data history to rule it as a direct connection with cancer of the mesothelium. From here on out, we’re going to assume there are four types as there is important information to learn about all four.
Types of Mesothelioma
Doctors diagnose mesothelioma based on the location of the tumor within the body; lungs, abdomen, heart, and testicles.
With that said, here are the four types:
Defined as an asbestos-related cancer of the mesothelium in the lungs. Tumors develop in the pleura which is the specific name of the lining that surrounds the lungs. It accounts for 3 out of 4 (75%) mesothelioma cancer diagnoses because most asbestos fibers are inhaled, which ultimately end up getting lodged into the lining of the lungs. The development of this particular asbestos-related cancer begins in the cells that line the sacs of the chest (pleura). Once the cancer cells develop further and invade the outer lining of the internal chest wall and lungs, it becomes known as pleural mesothelioma.
Tumors develop in the peritoneum, which is the name of the lining that surrounds the abdomen. Peritoneal accounts for approximately 20-25% of cases. How it is diagnosed – The abdominal cavity is lined with mesothelial cells that aid in protecting the organs so if an MRI or CT scan shows a thickening of this lining and of the small nodules, this indicates that a tumor may be present.
There are two ways how asbestos fibers reach the abdomen:
- It can be inhaled by breathing asbestos-contaminated air, which leads to the asbestos reaching the lungs, then traveling via-lymphatic ducts to the abdominal peritoneal lining.
- By swallowing saliva and/or food that is carrying the asbestos fibers, which takes the asbestos directly to the stomach and intestines.
The second to least common type is pericardial mesothelioma. With this type, tumors develop in the pericardium, which is the specific name of the lining that surrounds the heart. This is diagnosed when cancer cells invade the fluid sac lining that surrounds the heart (pericardium). This uncommon type usually occurs when the cancer cells spread from the lining of the lungs (pleura) to the lining of the heart. As the cancer cells progress and multiply, the heart is unable to efficiently produce oxygen to the rest of the body. This is what causes an extreme and rapid decline in health.
Tumors develop in the tunica vaginalis, which is the name of the lining that surrounds the testis and is the rarest form of the four types. It makes up less than one percent of all mesothelioma diagnoses. Normally, mesothelioma develops in the abdomen or chest, however, there have been rare occurrences in which it has developed in the testicles. As mentioned earlier, it originates in the tissues of the tunica vaginalis and thus far, only about 100 cases have ever been reported. This is a low number compared to the near 50,000 other asbestosis and asbestos-related cancer cases reported here in the United States alone. The pathway to the testicular region of the body is not yet understood because of the rarity of this disease.
Top 20 Common Misspellings of "MESOTHELIOMA"
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