Mesothelioma, cancer that develops after asbestos exposure, is not categorized as being found in a single area of the body like lung cancer or stomach cancer. Instead, it is broken down into four different common types and locations. Additionally, there are other, rarer types that depend on the location the cancer develops and its cell type.
The most common location for mesothelioma to form is in the lungs, but it can also be found in other parts of the body. Additionally, each mesothelioma type can cause different symptoms and treatments must be tailored depending on cell variety.
Common & Rare Mesothelioma Types
Here's an overview of the types of mesothelioma.
Common Types of Mesothelioma by Cell Type and Location:
- Pleural Mesothelioma, which occurs in the lungs
- Peritoneal Mesothelioma, which occurs in the abdomen
- Epithelioid Mesothelioma, found in epithelioid Cells
- Biphasic Mesothelioma, found in both epithelioid and sarcomatoid Cells
Rare Types of Mesothelioma by Cell Type and Location:
- Pericardial Mesothelioma, which occurs in the heart
- Testicular Mesothelioma, found in the testes
- Sarcomatoid Mesothelioma, found in sarcomatoid Cells
Additionally, there are other rare cell subtypes such as well-differentiated papillary cells, deciduoid, small cell, cystic, desmoplastic, adenomatoid, and heterologous cells.
Types of Mesothelioma By Location
Now let's take a closer look at these types of mesothelioma.
Pleural Mesothelioma (Lungs)
Being the most common type of mesothelioma, approximately 70-75% of mesothelioma cases occur in the pleura. The function of the pleura is to allow for optimal expansion and contraction of your lungs while breathing. It is a thin membrane that lines your chest cavity, covering the inside surface of your rib cage, and spreads over the lungs as well.
More research has been conducted for pleural mesothelioma than any other type of mesothelioma. While mesothelioma is not curable, it can be treated so that a patient lives the remainder of their life with less pain. Most of these patients qualify for chemotherapy or radiation therapy.
Symptoms of pleural mesothelioma can include:
- Shortness of breath
- Chest pain
- Weight loss
Peritoneal Mesothelioma (Abdomen)
10-20% of mesothelioma cases are peritoneal mesothelioma—cancer of the peritoneum (lining of the abdomen). While there is less research available related to this type of mesothelioma compared to pleural mesothelioma, the prognosis seems to be better. Severity depending, research shows that 52% of patients who have had surgery or heated chemotherapy tend to live five or more years after they've received diagnosis and treatment.
Symptoms of peritoneal mesothelioma can include:
- Abdominal swelling and pain
- Bowel changes
- Loss of appetite
Pericardial Mesothelioma (Heart)
Extremely rare, pericardial mesothelioma is a type of cancer found in the pericardium (lining of the heart). This is also one of the most aggressive forms of mesothelioma, with a prognosis ranging from six weeks to 15 months, with the average being a six-month life expectancy. It takes a massive toll on a person's heart.
Symptoms of pericardial mesothelioma can include:
- Chest pain
- Irregular heartbeat
- Difficulty breathing
Testicular mesothelioma is the rarest of all mesothelioma types and it develops in the tunica vaginalis (the lining covering the testes). The prognosis is two years, but treatments such as surgery and chemotherapy have the potential to increase a patient's prognosis past the two years.
Symptoms of testicular mesothelioma can include:
- Painless testicular lumps
- Scrotal swelling
Types of Mesothelioma Cells
There are three cell varieties of mesothelioma:
- Biphasic (a mix of the first two types)
These cell types can be identified under a microscope.
Each of these types responds differently to treatment. Epithelial cells are the most responsive to treatment, and sarcomatoid cells are more resistant, meaning that biphasic (being a mix of those) varies in its response to treatment. These differences are taken into account by medical professionals when they are determining a treatment plan.
Epithelial Cell Mesothelioma
Being the most common mesothelioma cell type, epithelial cell mesothelioma makes up approximately 70-75% of all asbestos-related cancer. Approximately 50% of pleural mesothelioma is epithelioid, and roughly 75% of peritoneal tumors are comprised of epithelial cells.
Epithelial cells have the best prognosis and are the most responsive to treatment. They are less aggressive and don't spread as quickly.
Sarcomatoid Cell Mesothelioma
The least common mesothelioma cell type is sarcomatoid mesothelioma (also called sarcomatous, spindle, or diffuse malignant fibrous mesothelioma), and it is the most aggressive and difficult to treat. 10-20% of all mesothelioma diagnoses are sarcomatoid. Approximately 20% of pleural tumors are sarcomatoid and a small 1% of peritoneal mesothelioma cases are.
Biphasic Cell Mesothelioma
Biphasic cell mesothelioma cases are dependent on which cell (epithelial or sarcomatoid) dominates the tumor. Typically, the presence of more epithelial cells indicates a better prognosis, while the presence of sarcomatoid cells usually indicates it will be harder to treat and an individual's prognosis won't be as good. Approximately 30% of pleural mesothelioma cases are biphasic and 25% of peritoneal tumors are as well.
Rare Mesothelioma Cell Types
The rare mesothelioma cell types are usually subtypes of the three cell types we covered above. They can be more difficult to diagnose and have characteristics that can affect a patient's prognosis. Here's an overview:
- Well-differentiated papillary cells: Commonly occur in peritoneal mesothelioma, with a very low amount of cases being reported elsewhere.
- Small cell: Occurs most commonly in the abdomen.
- Deciduoid: A little over half of deciduoid cases occur in the abdomen and the rest in the lung lining.
- Cystic cells: More common in peritoneal mesothelioma.
- Desmoplastic and lymphohistiocytic cells: More common in pleural mesothelioma cases.
- Adenomatoid cells: Occur in both benign and malignant mesothelioma cases.
- Heterologous cells: Found in tumors that may also contain cartilage, bone, and soft tissue.
Mesothelioma Symptoms by Type
Unfortunately, many of the early signs of mesothelioma can disguise themselves as minor ailments. Most patients with mesothelioma don't receive a mesothelioma diagnosis until months after their first symptoms arise. If you have any combination of these symptoms, you should see a doctor right away.
The types of symptoms you may have can vary depending on which type of mesothelioma you have, so we'll break it down by the different types. But here are the general symptoms of mesothelioma:
- Excessive sweating
- Unexplained weight loss
- Blood clots
- Loss of appetite
Symptoms of Pleural Mesothelioma
Pleural mesothelioma, or mesothelioma of the chest, makes up 80% of mesothelioma cases and can produce the following symptoms:
- Low grade fever
- Pain in the side of the chest or lower back
- Shortness of breath
- Dry Cough/Persistent Cough
- Lung fluid buildup (pleural effusion)
- Body aches
- Trouble swallowing (feeling like food gets stuck)
- Swelling of the face and arms
- Blood clots
Late-stage symptoms include:
- Night sweats
- Difficulty swallowing
- Coughing up blood
- Face or arm swelling
Symptoms of Peritoneal Mesothelioma
Peritoneal mesothelioma, or mesothelioma of the abdomen, makes up about 20% of mesothelioma cases and can produce the following symptoms:
- Abdominal pain
- Abdominal swelling
- Fluid in the abdomen
- Nausea and vomiting
- Constipation or other bowel issues
- Intestinal obstruction
- Weight loss
- Loss of appetite
Symptoms of Pericardial Mesothelioma
Pericardial mesothelioma, or mesothelioma of the heart, makes up less than 1% of mesothelioma cases and can produce the following symptoms:
- Chest pain
- Irregular heart rhythm
- Irritation and thickening of the pericardium
- Heart murmur
- Pericardial effusions (fluid buildup in the pericardium)
- Pericardial bleeding
- Shortness of breath or difficulty breathing
Getting a Mesothelioma Diagnosis
If you are experiencing any of the symptoms above and were exposed to asbestos, talk to your doctor right away. They'll use scans to detect abnormalities in your body and may require biopsies for definitive proof of mesothelioma.
After diagnosis, reach out to us. We could help get you compensation to cover your medical care and hold those responsible who negligently exposed you to the asbestos that caused your illness.
Your diagnosis will depend on your current stage of mesothelioma.
Staging of Mesothelioma
Doctors use three-staging systems to describe the spread of mesothelioma (not to be confused with the four stages of mesothelioma). These staging systems are typically used for identifying common lung cancers and can help the doctors determine how far the tumor has spread and which treatment options are available based on their findings.
These staging systems include:
- TNM: (T) refers to the growth of the tumor, (N) refers to the extent the tumor has spread to nearby lymph nodes, and (M) refers to the tumors spread to other organs.
- Brigham System: Doctors use this four-stage system to describe how the spread of the tumor affects their ability to surgically remove it.
- Butchart System: The most common and oldest staging method, doctors use this four-stage method to describe the location of the main tumor.
Stages of Mesothelioma, All Types
There are four stages of mesothelioma that are used by medical professionals to determine the progression of it and the best course of treatment. These stages are based on the size of the tumor and how far it has spread. Stage 1 usually has the best prognosis, while stage 4 is known as the end-stage of mesothelioma with the shortest average life expectancy. One of the main reasons mesothelioma can be so hard to be diagnosed is that the first two stages have less noticeable symptoms, while stages 3 and 4 have symptoms that usually lead to a diagnosis.
Stage 1 of Mesothelioma
In stage 1, the tumor is localized and hasn't spread. Most treatment options are available at this stage and a person's life expectancy is significantly better than in the later stages. This is a difficult stage to catch cancer because an individual may not be experiencing very many symptoms.
Stage 2 of Mesothelioma
In stage 2, the cancer cells have begun to enter nearby lymph nodes. The tumors remain small enough that they could be removed surgically, which will positively affect the patient's life expectancy.
Stage 3 of Mesothelioma
In stage 3, the tumor progression is evident in nearby organs and distant lymph nodes. Treatment options are more limited than in earlier stages, but certain therapies can help improve quality of life. If surgery is available, a patient could live many more years.
Stage 4 of Mesothelioma
In stage 4, the cancer cells have spread throughout the body cavity and to other organs. At this stage, most treatment options (including surgery) are no longer viable options, and palliative care is used to reduce the severity of symptoms. The median life expectancy for someone with stage 4 mesothelioma is typically 14 months or less.
This is the stage in which metastasis happens, where cancer has spread far from where it first developed. Unlike most other cancers, mesothelioma tends to only metastasize locally rather than distantly.
Treatment Options After Diagnosis
Depending on the stage that your mesothelioma is at, you may have the following available to you:
- Surgery (Available in Stages 1, 2, and rarely 3)
- Chemotherapy and Immunotherapy (Available in every stage)
- Radiation therapy (Available in every stage)
- Clinical trials (Dependent on your doctor)
It's always important to talk to your doctor about your options and to keep an open mind. They should be able to give you a good treatment plan that fits your stage of mesothelioma and will hopefully care for you to the best of their ability.