COVID-19 Update: Our team is ready to serve you. Get Your Free Mesothelioma Guide

Epithelioid Mesothelioma

Epithelioid mesothelioma, also known as epithelial mesothelioma, is the most common mesothelioma cell type, accounting for roughly 70% of all cases. Epithelioid mesothelioma cells spread at a relatively slow rate, causing them to respond well to treatments like surgery, chemotherapy, and radiation. For this reason, epithelial mesothelioma has a better prognosis than other cell types.

Learn About Your Diagnosis

What Is Epithelioid Mesothelioma?

Epithelioid or epithelial mesothelioma is one of three histological (cell) subtypes of this rare cancer. Histology is the study of cells and tissues under a microscope. The other two relatively common mesothelioma cell types are sarcomatoid and biphasic.

Healthy epithelioid mesothelioma cells typically develop from granuloma, a type of tissue formed as wounds heal. Asbestos — a durable but deadly mineral — can cause epithelioid cells to mutate, according to the UPMC Hillman Cancer Center.

Did You Know?

When asbestos-containing products are handled or disturbed, they can release microscopic fibers into the air. Nearby persons may breathe in or swallow these fibers without being aware of it. Once inside the body, the fibers can travel to the lining of the lung or peritoneum and other areas.

The human body cannot break down these asbestos fibers, and over time they may cause scarring and the formation of cancerous tumors.

Thankfully, epithelioid mesothelioma cancer generally responds well to treatments provided that doctors can diagnose this cancer before it spreads throughout the body. Patients typically live longer than if they had sarcomatoid or biphasic mesothelioma.

Quick Facts About Epithelioid Mesothelioma

  • Epithelial cells can appear in all types of mesothelioma.
  • Patients with epithelioid mesothelioma may be more likely to receive surgery when compared to the other cell types, according to a 2012 study published in the Ochsner Journal.
  • Pleural epithelial mesothelioma patients who received a combination of surgery, chemotherapy, and radiation had a median survival time of about 23 months, according to a 2017 study published in the Journal of Clinical Oncology.

Epithelioid Mesothelioma Symptoms

As with all types of mesothelioma, epithelioid mesothelioma typically presents with mild and vague symptoms. For this reason, it is sometimes mistaken for more common health problems with similar symptoms, like pneumonia or asthma.

According to Moffitt Cancer Center, one of the earliest symptoms of epithelial mesothelioma is a cough that won’t go away.

Other common symptoms of epithelioid mesothelioma include:

  • Chest pain
  • Fatigue
  • Shortness of breath
  • Unexplained weight loss

These mesothelioma symptoms appear in other cell types as well. For example, chest pain, a persistent cough, and shortness of breath are all early symptoms of sarcomatoid mesothelioma, according to Moffitt Cancer Center.

Without a proper diagnosis and treatment plan, these symptoms worsen as the cancer spreads throughout the body.

Epithelial Mesothelioma Diagnosis

To diagnose malignant (cancerous) epithelioid mesothelioma, doctors follow a multi-step process.

This process includes:

  1. Ruling out other conditions: Doctors will first see if more common health problems could be the cause of the symptoms. They may also actively look for possible signs of mesothelioma, such as pleural effusions (fluid buildup in the lung lining).
  2. Imaging Tests: Doctors can use imaging tests such as X-rays, magnetic resonance imaging (MRI) scans, or computed tomography (CT) scans to look for tumors, scar tissue, or other health problems associated with mesothelioma.
  3. Biopsy: Imaging tests can not conclusively diagnose mesothelioma. If doctors believe that cancer could be the cause of your symptoms, they will request a biopsy. Through a biopsy, a specialist takes a tissue or fluid sample of the affected area and examines it under a microscope to see if cancer cells are present.

The only way to confirm a mesothelioma diagnosis is through a biopsy since doctors need to see and identify the specific cells that make up cancerous tumors and growths.

Specialists should also test biomarkers to distinguish these cells from other similar illnesses (such as lung and ovarian cancer). Biomarkers are measurable substances within the body that appear when certain diseases or infections are present.

Did You Know?

Common epithelioid mesothelioma biomarkers include proteins such as calretinin and thrombomodulin.

Once a mesothelioma diagnosis is made, doctors can determine if the malignant cells belong to an epithelioid cell subtype.

If you or a loved one has received a mesothelioma diagnosis, you may be able to access compensation.

Rare Types of Epithelial Mesothelioma Cells

According to Moffitt Cancer Center, there are several subtypes of epithelioid mesothelioma. Some of these subtypes are extremely rare and, in some cases, benign (non-cancerous).

Subtypes of epithelial mesothelioma include:

  • Adenoid Cystic Mesothelioma

    Cystic cells are rare and not fully understood. They are often benign and don’t usually spread to distant sites.

  • Adenomatoid Mesothelioma

    Adenomatoid, also known as glandular epithelioid subtype, is very rare and generally originates within a patient’s genital glands.

  • Deciduoid Mesothelioma

    Deciduoid cells are characterized by their distinct borders and large oval shapes. This type of mesothelioma is associated with a very poor prognosis, according to the British Medical Journal (BMJ).

  • Papillary Mesothelioma

    According to a 2017 report published in Cureus, this subtype is much more common in women than men and is slow to progress. It is also rarely linked to asbestos exposure, unlike almost all other types of mesothelioma.

  • Small-Cell Mesothelioma

    Small-cell mesothelioma is an extremely rare subtype that can often be mistaken for other small-cell cancers, according to a paper published in the journal Diagnostic Cytopathology. The name of this epithelioid subtype points to its cells’ uniform but small nature.

Identifying the cell subtype can give doctors a better idea of how long a patient can expect to live with malignant epithelioid mesothelioma, since the subtypes may grow at different speeds and respond uniquely to treatments.

Epithelioid Mesothelioma Prognosis

A prognosis is the expected outcome of a disease. Though all forms of mesothelioma are deadly, epithelioid mesothelioma generally has the best prognosis of all three cell subtypes.

Average Epithelioid Mesothelioma Prognosis

Those with epithelial mesothelioma typically live 1-2 years following diagnosis.

This cell type has a relatively good mesothelioma prognosis because of how the cancer cells grow. These cells tend to grow at slower rates than other mesothelioma cell types and not spread as quickly, as noted by both the British Lung Foundation (BLF) and the American Society of Clinical Oncology (ASCO).

Other factors can also impact a mesothelioma patient’s prognosis.

These factors include:

  • Age: Older patients may have other health problems that make them weaker or prevent them from receiving certain treatments, such as surgery. If a patient cannot receive aggressive treatments, his or her prognosis may be worse.
  • Cancer stage: If the cancer is detected before it has spread, it can be treated more easily.
  • Tumor location: Peritoneal mesothelioma (which develops in the abdominal lining) has a better prognosis than pleural mesothelioma (which develops in the lung lining), pericardial mesothelioma (which develops in the heart lining), or testicular mesothelioma.

Mesothelioma specialists take each of these factors into account when giving patients a prognosis. Specialists also use these factors to determine the best course of treatment for patients.

Epithelioid Mesothelioma Treatment

An important factor that affects mesothelioma prognosis and survival times is treatment. Fortunately, epithelioid mesothelioma cells are more responsive to treatments than the other cell types, according to Moffitt Cancer Center.

Like all forms of this cancer, epithelial mesothelioma is typically treated using surgery, chemotherapy, and radiation. Treatments can vary depending on the patient’s needs, but generally speaking, a combination of these treatments will be used.

Below, get a breakdown of each type of mesothelioma treatment.


Through chemotherapy, patients intravenously receive drugs that kill cancerous cells and tumors.

Common chemotherapy drugs for mesothelioma include:

  • Pemetrexed
  • Cisplatin
  • Carboplatin
  • Gemcitabine

Epithelioid mesothelioma cells often respond better to chemotherapy due to their slower growth rate, according to ASCO.

Multiple rounds of mesothelioma chemotherapy may be needed to get a good response.


Doctors may also use radiation therapy to prevent epithelioid mesothelioma cells from dividing.

Mesothelioma radiation therapy is administered by a machine that delivers high-energy electrons to the tumor site, which causes the cells to die and the tumors to shrink.

According to the UPMC Hillman Cancer Center, radiation may be used to supplement a surgery or as a main course of treatment if surgery is not an option.


Surgery is often an effective way to treat mesothelioma because removing tumors prevents the spread of the cancer and leaves less of it for other treatments to impact.

If the epithelial mesothelioma cells develop in the lining of the lungs, patients may qualify for one of several types of surgeries.

These surgeries include:
  • Extrapleural Pneumonectomy (EPP)

    This surgery removes cancerous tumors in the affected lung, pleura (lung lining), diaphragm, and lymph nodes. This extensive operation is mainly used on patients if the epithelioid mesothelioma has not begun to spread, according to the American Cancer Society (ACS).

  • Pleurectomy with Decortication (P/D)

    This surgery removes cancerous tumors, the pleura, and diaphragm closest to the mesothelioma tumors, but does not remove the lung. This can allow patients to recover with a lower risk of extreme complications.

An EPP is not usually recommended if the cancer has advanced throughout the body or if the patient has other health problems, but a P/D may still be an option in some cases.

Other mesothelioma surgeries may be used to remove cancerous tumors and organ linings if the cancer develops in the peritoneum (abdomen lining) or pericardium (heart lining).

For example, patients with peritoneal epithelioid mesothelioma may receive cytoreduction surgery with HIPEC. Through this surgery, doctors remove all visible cancer tumors and then bathe the peritoneum with heated chemotherapy drugs.

Multimodal Therapy and Survival Times

When the mesothelioma treatments above are combined, it is known as multimodal therapy. Research has shown that multimodal therapy can help improve the long-term survival rates of patients with epithelial mesothelioma.

For example, the Dana Farber Cancer Institute studied the lifespans of patients who underwent EPPs and received adjuvant (supplemental) radiation and chemotherapy.

Patients with epithelioid mesothelioma lived longer than those with other cell types, as 65% were still alive after 2 years, and 27% were alive after 5 years.

To learn if you’re eligible for compensation to help pay for treatment, get a free case review.

Other Treatment

Outside of the standard treatment options listed above, patients with epithelioid mesothelioma may qualify for new treatments through clinical trials.

For example, upcoming treatment options (such as new drugs or treatment combinations) are tested in mesothelioma clinical trials with the hopes of improving survival rates and finding a cure.

Patients interested in joining a clinical trial should speak with their doctor. Clinical trials have strict requirements depending on what is being studied, so not every patient will qualify.

Hope for Victims of Epithelioid Mesothelioma

Epithelial mesothelioma patients may find hope in knowing that this cell type typically responds well to treatments. Further, survival times may increase over time as new treatments continue to be tested.

That said, a diagnosis can be frustrating or scary — you never expected to develop mesothelioma, and you may be wondering how to provide for your family while you seek medical treatment.

Thankfully, there are options available. Learn how we can help you navigate life after an epithelioid mesothelioma diagnosis.

Mesothelioma Support Team
Reviewed by:Dr. Mark Levin

Certified Oncologist and Hematologist

  • Fact-Checked
  • Editor

Mark Levin, MD has nearly 30 years of experience in academic and community hematology and oncology. In addition to serving as Chief or Director at four different teaching institutions throughout his life, he is also still a practicing clinician, has taught and designed formal education programs, and has authored numerous publications in various fields related to hematology and oncology.

Dr. Mark Levin is an independently paid medical reviewer.

Stephanie KiddWritten by:


Stephanie Kidd grew up in a family of civil servants, blue-collar workers, and medical caregivers. Upon graduating Summa Cum Laude from Stetson University, she began her career specializing in worker safety regulations and communications. Now, a proud member of the American Medical Writers Association (AMWA) and Editor-in-Chief of the Mesothelioma Justice Network, Stephanie serves as a voice for mesothelioma victims and their families.

View 20 Sources
  1. American Cancer Society. (n.d.). How Is Malignant Mesothelioma Diagnosed? Retrieved March 23, 2020, from
  2. American Cancer Society. (n.d.). What Is Malignant Mesothelioma? Retrieved March 23, 2020, from
  3. American Cancer Society. (n.d.). Chemotherapy for Malignant Mesothelioma. Retrieved March 23, 2020, from
  4. American Cancer Society. (n.d.). Surgery for Malignant Mesothelioma. Retrieved March 23, 2020, from
  5. Bazine, A., Fetohi, M., Namad, T., Benzekri, A., Zainoun, B., Tanz, R., & Ichou, M. (2017, March 19). A Case of Well-Differentiated Papillary Mesothelioma of the Male Peritoneum: Successful Treatment by Systemic Chemotherapy. Retrieved March 23, 2020, from
  6. British Lung Foundation. (2020, January 16). What is mesothelioma? Retrieved March 25, 2020, from
  7. Epithelial Mesothelioma. (n.d.). Retrieved March 23, 2020, from
  8. Hai, B., Yang, Y., Xiao, Y., Li, B., & Chen, C. (2012, December). Diagnosis and prognosis of malignant mesothelioma of the tunica vaginalis testis. Retrieved March 25, 2020, from
  9. Inai, K. (2008, March). Pathology of mesothelioma. Retrieved March 23, 2020, from
  10. Makarawate, P., Chaosuwannakit, N., Chindaprasirt, J., Ungarreevittaya, P., Chaiwiriyakul, S., Wirasorn, K., … Sawanyawisuth, K. (2013). Malignant mesothelioma of the pericardium: a report of two different presentations. Retrieved March 25, 2020, from
  11. Moffitt Cancer Center. (n.d.). Epithelial Mesothelioma. Retrieved March 23, 2020, from
  12. Mott, F. E. (2012). Mesothelioma: a review. Retrieved March 25, 2020, from
  13. Nelson, D. B., Rice, D. C., Niu, J., Atray, S., Vaporciyan, A. A., … Antonoff, M. (2017, August 17). Long-Term Survival Outcomes of Cancer-Directed Surgery for Malignant Pleural Mesothelioma: Propensity Score Matching Analysis. Retrieved March 25, 2020, from
  14. NYU Langone Health. (n.d.). Types of Malignant Mesothelioma. Retrieved March 23, 2020, from
  15. Pacific Heart, Lungs, & Blood Institute. (n.d.). Mesothelioma Cell Types. Retrieved March 23, 2020, from
  16. Taylor, L., Cooper, D., & Aujayeb, A. (2019, July 1). Malignant deciduoid mesothelioma: a rare variant of epithelioid mesothelioma. Retrieved March 23, 2020, from
  17. Texas Oncology. (n.d.). Radiation Therapy for Malignant Pleural Mesothelioma. Retrieved March 23, 2020, from
  18. Turk, J. L., & Narayanan, R. B. (1982, April). The origin, morphology, and function of epithelioid cells. Retrieved March 23, 2020, from
  19. UPMC Hillman Cancer Center. (n.d.). Mesothelioma Types, Risks, Diagnosis, & Treatment: UPMC. Retrieved March 23, 2020, from
  20. Zhang, Y., Afify, A., Gandour-Edwards, R. F., Bishop, J. W., & Huang, E. C. (2016, June). Small cell mesothelioma: A rare entity and diagnostic pitfall mimicking small cell lung carcinoma on fine-needle aspiration. Retrieved March 23, 2020, from
Back to Top