There are different types of mesothelioma based on the types of cells found in the cancer. Ask your doctor at the time of diagnosis of mesothelioma what type of cell type you have.
What Are the Different Mesothelioma Cell Types
These are the three mesothelioma cell types. The type of mesothelioma you have can make a big difference in how the cancer is treated.
- Epithelioid Mesothelioma
- Sarcomatoid Mesothelioma
- Biphasic Mesothelioma
The type of mesothelioma you have can make a big difference in how the cancer is treated. What it means to have each subtype of mesothelioma:
Epithelioid mesothelioma is the most common type of mesothelioma, making up about 50-70 percent of all cases. It means your cancer is made from epithelial cells, which are cells that line different kinds of tissues, such as pleural tissue. If you have this type of cancer, you tend to live longer than those with either sarcomatoid mesothelioma or biphasic mesothelioma. This type of mesothelioma has had the most research done on it so there is a better understanding as to what kind of treatment works best. You also may have a greater chance of getting into a clinical trial if you have epithelioid mesothelioma.
The epithelioid cells in the body are normally responsible for sensing things in the environment, protection of organs in the body, and fluid secretion. You have epithelioid cells in virtually all parts of your body, including your skin and internal organs. If you have epithelioid mesothelioma, you are more likely to find this in malignant pleural mesothelioma as opposed to peritoneal mesothelioma.
To get a diagnosis of epithelioid mesothelioma, doctors must actually get a sample of the tissue through a needle biopsy or through a biopsy during a thoracoscopy. Under the microscope, the cancerous cells can be identified as epithelioid cells, making it clear that this is the type of cancer you have. Epithelial cells can look like other types of cancer, making it important for doctors to be aware that mesothelioma is suspected to avoid misdiagnosis.
If you don’t know whether or not you have epithelioid cell mesothelioma, ask your doctor to give you a copy of your pathology report. This will be a detailed explanation of what the cells look like and will tell you the pathologist’s opinion as to what kind of cancer you have.
Learn More About Epithelioid Mesothelioma
This type of mesothelioma is the least common and the most difficult to treat. It often looks like other types of cancer under the microscope, making it hard to diagnose. Only about 7-20 percent of all cases of mesothelioma are of the sarcomatoid type. In the past, this type of cancer has been called “spindled mesothelioma,” “sarcomatoid mesothelioma” or “diffuse malignant fibrous mesothelioma”. Rather than the cube-shaped epithelioid cells, sarcomatoid cells in mesothelioma are elongated, large, and spindle-shaped.
Sarcomatoid mesothelioma can be of the pleural or peritoneal type. Like epithelioid mesothelioma, it is caused by asbestos. It is very aggressive and spreads easily.
Because of the appearance of the cancer, it often mimics other cancers and even benign conditions, such as fibrous tumors of the lining of the lung. It can also look like sarcoma, which is a type of cancer affecting many other body areas. There are not as many good treatment choices with sarcomatoid mesothelioma and the response to the available treatments isn’t as good as with epithelioid mesothelioma.
Sarcomatoid mesothelioma is diagnosed by doing a CT scan of the chest or MRI scan. If the scan looks like cancer is present, a sample is taken by doing a thoracoscopy, which is a way to see the lung tissue using a camera and a flexible tube. The sample is looked at under the microscope to see what kind of cancer it is. Doctors sometimes use immunohistochemistry, which is a test that looks at antibodies specifically for mesothelioma cells under the microscope. The antibodies bind to the mesothelioma cells and specific stains help them show up under microscopic examination.
Common symptoms of sarcomatoid mesothelioma include:
- Unexplained weight loss
- Shortness of breath
- Nausea and a lack of appetite
- Swelling of the abdomen
The treatment of sarcomatoid mesothelioma depends on the stage of the mesothelioma and where the cancer is located. Surgery, radiation therapy, and chemotherapy are the same as with other types of mesothelioma.
Learn More About Sarcomatoid Mesothelioma
Biphasic mesothelioma is a type of cancer that has a combination of epithelioid and sarcomatoid cancer cells in it. The more epithelioid cells you have in the mixture, the longer your time of survival is likely to be. Biphasic mesothelioma is the second most common kind of mesothelioma, making up about 20-35 percent of all mesothelial cancers. Most of the biphasic mesothelioma patients have disease in the pleural lining of the lung. This type of cancer is caused by exposure to asbestos.
While having more epithelioid cancer cells in the tumor is considered a good thing, it may only affect your prognosis by a few months. The epithelioid cell areas and the sarcomatoid cell areas may be near to each other or separate from each other on a biopsy sample of the cancer.
It can be difficult to diagnose biphasic mesothelioma because biopsy samples usually only take a small piece of the tumor and may miss the biphasic aspect of the condition, showing only epithelioid cells or sarcomatoid cells on the biopsy. Sometimes it takes getting a larger sample of the tumor in order to identify the cancer as being biphasic. As with other types of mesothelioma, sometimes immunohistochemistry needs to be done in order to make sure the cancer is really mesothelioma. Some people only find out they have biphasic disease after the tumor is removed completely during surgery.
Treatment of biphasic mesothelioma involves surgery, chemotherapy, and radiation. The stage of the mesothelioma determines the disease treatment. Rarely is just one type of therapy used and many people have two types off treatment or all three, depending on the location of the tumor and on the response to therapy.
Learn More About Biphasic Mesothelioma