What is Mesothelioma?
Mesothelioma is a rare, aggressive form of cancer that is caused by a person either inhaling or ingesting tiny asbestos fibers. Once these fibers have entered the body via esophageal or tracheal pathways, they will become lodged in the protective lining that covers our internal organs. This lining is known as the mesothelium.
The mesothelium consists of two layers:
- The inner layer of the mesothelium wraps around major organs like the lungs, abdomen, and heart.
- The outer mesothelium layer forms a sac that surrounds the inner layer; mesothelioma grows in between or on these linings.
There are three types of mesothelioma a person could develop and the name is specifically associated with the location of where the tumor is found. For instance:
- Pleural Mesothelioma: Tumors develop in the pleura which is the location specific name of the mesothelium lining that surrounds the lungs.
- Peritoneal Mesothelioma: Tumors develop in the peritoneum which is the location specific name of the mesothelium lining that surrounds the abdomen.
- Pericardial Mesothelioma: Tumors develop in the pericardium which is the location specific name of the mesothelium lining that surrounds the heart.
Mesothelioma cancer is categorized and named based on the location of the cancer found in the body. There are four types of mesothelioma which can be broken down into two categories; common and uncommon.
Common types are:
- Pleural Mesothelioma (pleura): This is a cancer that affects the lungs’ mesothelium. It is the most common type and it accounts for three out of every four cases diagnosed.
- Peritoneal Mesothelioma (peritoneum): This affects the mesothelium that surrounds the abdomen. It accounts for approximately 20 – 25%% of all cases.
About 75% of mesothelioma cases begin in cells that line the sacs of the chest, the pleura, which is the outer lining of the internal chest wall and lungs. Because the tissue which covers the heart (pericardium) is close to the pleura, this cancer sometimes spreads to the lining of the heart.
The lining of the abdominal cavity is called the peritoneum. It contains fluid which aids in keeping the contents of abdomen safe and accounts for approximately 25% of mesothelioma cases. This type of asbestos-related cancer usually does not spread to other parts of the body.
The least common type is pericardial mesothelioma which involves the heart. Cancer invades the sac which surrounds the heart (pericardium). As it progresses, the heart is unable to get oxygen to the body efficiently. This causes a rapid decline in health.
Also known as, tunica vaginalis, is the rarest type out of the four and it affects the lining of the testicles. Very rarely will this asbestos-related cancer arise in the lining that surrounds the testis. In fact, it is so rare that there are not even enough medical cases to determine that asbestos is the actual cause of cancer in the tunica vaginalis.
Even though there are four types of mesothelioma, it can be claimed that they are all caused by one resounding factor.
What Causes Mesothelioma?
Mesothelioma has been associated with prolonged exposure to asbestos fibers or dust. Asbestos is a mineral that occurs naturally and it was an extremely popular material in the construction and automotive industries during the 20th century. The reason for its popularity was because of its insulating and heat resistance properties. Once asbestos-containing materials are disturbed, they release asbestos fibers, which then go airborne and then are eventually inhaled or ingested by the nearby persons. These fibers eventually lodge themselves in the different mesothelium locations where the body cannot expel them.
Over time, these fibers agitate or damage mesothelial cells. This irritation or damage turns otherwise healthy mesothelial cells into abnormal cells that then begin to replicate uncontrollably. As briefly stated in the first paragraph of this page, this uncontrollable replication of damaged cells cause tumors to grow on the mesothelium and this is how mesothelioma is developed.
Each of the four types of mesothelioma can portray different symptoms and warning signs. The difference of symptoms depends on the:
- Type of mesothelioma
- Molecular cell type
- The stage at which it was diagnosed.
With four types of mesothelioma, three various cell types, and four stages of severity, a patient could experience a wide variety of symptoms. Mesothelioma staging determines the severity of this disease and the most appropriate treatment options for the patient.
It is important to be aware of what type of body changes can signify a potential problem. This asbestos-related cancer is difficult to diagnose and often is not recognized until the disease has reached the later stages. Many people and doctors mistake the symptoms and warning signs for other common illnesses such as a cold or upper respiratory infection. If you have been exposed to asbestos, don’t wait until your symptoms have a negative impact on your life before you see a physician. The stage of cancer at the time of diagnosis determines life expectancy. It has been reported that about 25% of patients that have complained of dyspnea and chest pain waited up to 6 months before they saw a doctor.
Who Can Develop Mesothelium Cancer?
Because asbestos was largely used in commercial and industrial products, people who work in factories, insulation manufacturing plants and ship building companies are the most likely to develop this type of cancer. Family members of these workers are also at risk because it is very likely and not uncommon for the asbestos fibers and dust to latch on to clothes of the workers and can then be carried home. People in property remodeling industries are also likely to develop mesothelioma since some buildings were made using asbestos containing materials. These materials can release asbestos fibers when disturbed or knocked down during the remodeling or demolition processes.
Average Age of Mesothelioma Diagnosis’s
The average age of a person diagnosed (this number includes all 4 types) is 61 years old. Out of all of these cases, 80% of them died after the age of 65. Although it is possible for mesothelioma to occur in young adults, it is very unlikely because it is rarely found in people under the age of 45. Be aware that as a person gets older, technically they are more at risk of being diagnosed with this form of cancer. This asbestos-related cancer as a latency period of anywhere between 20-50 years to start showing it’s symptoms so just because you are not showing any warning signs right now, it doesn’t mean you haven’t inhaled or ingested asbestos in the past.
Are Males or Female’s more at risk?
Studies have shown that men are diagnosed with this cancer considerably more than compared to women. A theory for this is likely due to men having the professions and jobs that exposed them to much more asbestos.
Histology of Mesothelium Cancer
Doctors diagnose mesothelioma in two ways. One, by where it is discovered in the body, and two by examining the structure and type of cells. There are various subtypes of pleural, peritoneal, pericardial, and testicular mesothelioma based on the cells. By examining the cell structures, doctors will then be able to determine the cell type. The information they obtain will help better predict what the cancer’s progression will be, the likely response to treatment, and the patient’s possible life expectancy. View the features / structures of the three types of mesothelioma cells.
Epithelioid – This cell type accounts for 50 – 70% of all cases which is considerably the most common along with a better prognosis compared to the other two types below.
Sarcomatoid – This cell type occurs approximately 10 – 20% of all mesothelioma cases. This one is known to be the most aggressive, most rare, and offers the worst possible prognosis.
Biphasic – (Mixed Type) This cell type contains characteristics of both sarcomatoid cells and epithelial cells. Approximately 30 percent of all cases are made up of biphasic cells.
Mesothelium Cancer Stages
Doctors and mesothelium specialists use four primary stages to determine the seriousness of a diagnosis. Staging is also the way doctors describe the cancer to patients and to one another about how advanced the cancer is, how many tumors there are and how far the cancer has spread within the body.
The four stage are described as, stage l, ll, lll, or lV. A lower number means you have more treatment options and a better chance for long-term survival.
Mesothelioma Prognosis & Life Expectancy
Malignant mesothelioma is a very aggressive disease, and unfortunately, it is usually not noticed until it is very late in either the 3rd or 4th stage. This results to unfavorable prognoses for everyone around the world that is diagnosed with mesothelioma. Although new innovative treatments are showing to be promising, there still is no cure for mesothelioma. The best way to start improving your prognosis and life expectancy is to find a doctor that specializes in your particular type of mesothelioma (Pleural, Peritoneal, or Pericardial). Preferably, one with experience in multimodal treatments to start assessing the various treatments available immediately.
Mesothelioma Treatments & Therapies
Once a diagnosis has been made the patient and doctor can begin to discuss the various treatment options. There are several types of treatments available including but not limited to: chemotherapy, radiation therapy, surgery, immunotherapy, a combination of the 4 (multimodal therapy), virotherapy, and clinical trials. While these are the more common treatments, you should always discuss complementary therapies with your physician as well. The treatment received will be decided on factors such as age, overall health, and severity / extent of the cancer.
Mesothelioma Doctors & Specialists
If you want to do a search for cancer specific specialists, we recommend starting with, “oncologists.” These doctors are recognized physicians who specialize in the diagnosis, prognosis, and treatment of cancer altogether. When someone dear to you is threatened by this 100% disabling disease, finding a mesothelioma doctor that you can trust is probably at the top of the list. To help jump-start your search and filter through the good and the bad, view our compilation of some of the best cancer physicians in the nation.
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