What Is Epithelioid Mesothelioma?
Epithelioid mesothelioma (also known as epithelial mesothelioma) is one of the three cell types of malignant mesothelioma. The other two mesothelioma cell types are sarcomatoid and biphasic.
Epithelial cells are a type of cell that lines the surfaces of your body. They are found on your skin, blood vessels, urinary tract, and organs. Healthy epithelial cells also typically develop from a type of tissue that forms as wounds heal (granuloma).
However, epithelial cells can mutate into mesothelioma tumors when they are exposed to asbestos fibers.
Epithelioid mesothelioma characteristics:
- Adhere together in clumps
- Clearly visible nucleus
- Move slowly
- Square, cubed, or flat-shaped cells
Malignant epithelioid mesothelioma cancer generally responds well to treatment. Patients with this cell type tend to live longer than patients with biphasic or sarcomatoid mesothelioma, provided that doctors can diagnose their cancer before it spreads.
Epithelioid Mesothelioma Symptoms
Epithelioid mesothelioma usually causes mild symptoms at first. Many times, the cancer is commonly mistaken for other health problems with similar symptoms, such as pneumonia or bronchitis.
Signs and symptoms of epithelial mesothelioma can vary depending on the location of cancer in the body.
Patients with epithelioid pleural mesothelioma (which forms in the lining of the lungs) will have different symptoms than those with epithelioid peritoneal mesothelioma (which forms in the lining of the abdomen).
Symptoms of Epithelioid Pleural Mesothelioma
- Chest pain
- Fatigue
- Shortness of breath
- Fluid buildup in the chest (pleural effusions)
Symptoms of Epithelioid Peritoneal Mesothelioma
- Abdominal pain
- Night sweats
- Unexplainable weight loss
- Fluid buildup in the abdomen (ascites)
Mesothelioma symptoms become more obvious and severe as the cancer spreads. Patients may be able to live longer if the cancer is diagnosed and treated early on.
Get our free Mesothelioma Guide to learn more about mesothelioma diagnosis, prognosis, and treatment options.
Epithelial Mesothelioma Diagnosis
Generally, a malignant epithelioid mesothelioma type diagnosis begins when a patient complains of symptoms. Doctors will then follow several steps to see if epithelioid mesothelioma is causing the symptoms.
Learn more about the epithelial mesothelioma diagnosis process below.
Physical Examination
Doctors will first perform a physical examination to determine the cause of the symptoms.
Many symptoms of epithelioid mesothelioma can be mistaken for less severe and more common illnesses. A physical examination can help doctors rule out other conditions.
If you are showing signs of mesothelioma, your doctor may ask you about any instances of asbestos exposure (which is the only known cause of mesothelioma).
Imaging Tests
If doctors think you may have cancer based on your physical exam, they will use imaging tests to look for tumors, scar tissue, or other signs of mesothelioma.
Imaging tests may include X-rays, MRI (magnetic resonance imaging) scans, CT (computed tomography) scans, or PET (positron emission tomography) scans.
Imaging tests are crucial as they can show where possibly cancerous tumors are located in your body.
Blood Tests
Doctors may order blood tests to diagnose epithelial mesothelioma or look for other conditions.
Through these tests, doctors will look at certain biomarkers (levels of certain substances within the blood) which may mean that mesothelioma is present. This helps doctors distinguish mesothelioma cells from cells of other, similar illnesses and avoid misdiagnosis.
According to the American Society of Clinical Oncology (ASCO), the diagnostic process for epithelioid mesothelioma should include immunohistochemistry staining, a type of biomarker test. This allows doctors to look for certain proteins (such as calretinin) and other signs of mesothelioma cancer.
Biopsy
If doctors find signs of cancer in imaging and blood tests, they will order a biopsy. A biopsy is the only way to confirm a mesothelioma diagnosis.
Doctors will collect small fluid or tissue samples from possibly cancerous tissue through a small needle and examine it under a microscope to see if mesothelioma cells are present.
Once the doctor confirms the presence of mesothelioma, they can see if the cells are epithelioid cells.
Epithelioid Mesothelioma Prognosis
Patients with epithelial mesothelioma typically have a life expectancy of 1-2 years following their diagnosis.
Epithelioid mesothelioma generally has a better prognosis (expected outcome of a disease) than the sarcomatoid and biphasic cell subtypes since epithelial cells spread fairly slowly.
The table below details epithelioid patient survival compared to the other mesothelioma cell types.
Mesothelioma Cell Type | Median Survival |
---|---|
Epithelioid | 14 months |
Sarcomatoid | 4 months |
Biphasic | 10 months |
Other factors such as the patient’s age, cancer stage, and mesothelioma type can also affect a prognosis. Mesothelioma specialists take all of these factors into account when determining a patient’s prognosis and deciding on the best treatment options.
Epithelial Mesothelioma Treatment
Like all forms of mesothelioma, epithelial mesothelioma is usually treated with surgery, chemotherapy, radiation therapy, and/or other cancer treatments.
Epithelial cells are more responsive to more aggresive mesothelioma treatments than other cell types.
Learn more about types of epithelioid mesothelioma treatment below.
Surgery
Removing tumors through surgery is the most effective way to treat epithelioid mesothelioma as most or all visible signs of the cancer are removed.
Patients with the epithelioid cell type are more likely to qualify for mesothelioma surgery compared to patients with sarcomatoid cells or biphasic tumors.
The most common surgeries for patients with epithelioid pleural mesothelioma include:
- Extrapleural pneumonectomy (EPP) (pleural mesothelioma)
- Pleurectomy with decortication (P/D) (pleural mesothelioma)
- Cytoreduction with HIPEC (peritoneal mesothelioma)

Did you know there’s financial assistance for treatment? Chat now for more information.
Chemotherapy
Chemotherapy for epithelioid mesothelioma is administered intravenously to stop cancer cells from spreading. Patients will typically need multiple rounds of mesothelioma chemotherapy.
Common chemotherapy drugs for mesothelioma include pemetrexed, cisplatin, carboplatin, and gemcitabine.
Radiation Therapy
Mesothelioma radiation therapy is administered by a machine that delivers high-energy waves to the tumor site which causes the epithelioid mesothelioma cells to die and the tumors to shrink.
Radiation may be used to supplement a surgery or as a main treatment if surgery is not an option.
Multimodal Therapy
Mesothelioma treatments are often combined in what’s known as multimodal therapy for best results.
Research has shown that multimodal treatment can improve the long-term survival rates of epithelioid mesothelioma patients.
According to a 2017 study, patients with epithelioid malignant pleural mesothelioma who received a combination of extrapleural pneumonectomy surgery (EPP), chemotherapy, and radiation lived for 23 months on average.
Emerging Treatment Options
In addition to the traditional cancer treatment methods, epithelial mesothelioma patients may be able to get other types of treatment as well.
Patients with epithelioid mesothelioma can access promising new treatment options through clinical trials, which test emerging treatments to hopefully improve survival rates and find a cure.
Treatment options such as gene therapy, cryotherapy, and others are becoming more available for mesothelioma patients thanks to clinical trials. Further, mesothelioma immunotherapy was recently approved as a mainstream treatment after promising results in clinical trials.
Use our free Mesothelioma Specialist Match program today to find available treatment and help you fight this disease.
Rare Types of Epithelial Mesothelioma Cells
There are several subtypes of epithelioid mesothelioma. Some of these subtypes are extremely rare and may even be non-cancerous (benign).
These subtypes grow at different speeds and respond differently to treatments. Identifying a patient’s epithelioid mesothelioma subtype allows oncologists to provide them with a more accurate prognosis.
Rare subtypes of epithelioid mesothelioma include:
- Adenoid cystic mesothelioma: These rare and often benign cells do not spread to distant areas of the body
- Adenomatoid mesothelioma: This subtype generally originates within a patient’s genital glands and accounts for roughly 6% of epithelioid pleural mesothelioma cases
- Deciduoid mesothelioma: This subtype is characterized by its distinct borders and large oval shapes and often has a very poor prognosis
- Papillary mesothelioma: These cells are more common in women than men and slow to progress
Small-cell mesothelioma: This extremely rare subtype is often mistaken for other small-cell cancers
Find Epithelioid Mesothelioma Treatment Today
Epithelial mesothelioma patients may find hope in knowing this cell type typically responds well to treatments.
If you have been recently diagnosed with epithelioid mesothelioma, you may still have questions or concerns about seeking treatment.
Thankfully, there are many mesothelioma specialists available to help you get treatment for epithelial mesothelioma. These treatments may include surgery, chemotherapy, radiation therapy, and more.
Use our free Mesothelioma Specialist Match program to find a specialist near you today.
Epithelioid Mesothelioma FAQs
What is epithelioid mesothelioma?
Epithelioid mesothelioma is one of three cell types of mesothelioma in addition to sarcomatoid and biphasic.
Epithelial mesothelioma has the best prognosis of all cell types because the cells are flat and grow more slowly.
What causes epithelioid mesothelioma?
The only known cause of epithelial mesothelioma is asbestos exposure.
Asbestos is a dangerous, naturally occurring mineral used for its durability from the 1930s to the early 1980s. Manufacturers of asbestos-based products knew the dangers but kept it secret in order to continue making profits.
Unfortunately, many exposed to asbestos have developed mesothelioma as a result.
What is the life expectancy for epithelial mesothelioma?
The average life expectancy for epithelioid mesothelioma patients is 1-2 years after their initial diagnosis.
Thankfully, there are several treatment options available for epithelioid mesothelioma patients to potentially extend their life expectancy such as chemotherapy, surgery, radiation, and more.
Where can I get treatment for epithelioid mesothelioma?
The best way to access epithelioid mesothelioma treatment is to work with a mesothelioma specialist. Doctors with experience in treating others with your condition can provide quality care to help you fight your disease.
To find an epithelioid mesothelioma specialist near you, use our free Mesothelioma Specialist Match program.