Epithelioid Mesothelioma

What Is Epithelial Mesothelioma?

Epithelial, or epithelioid, mesothelioma cancer is the most common of this cancer’s three cell types. The epithelium is a protective layer of cells that line the outer surface of organs, blood vessels and cavities. Asbestos fibers irritate these cells and are the primary cause of epithelioid mesothelioma.

Epithelial mesothelioma can develop in the lining of the lungs (pleural), abdomen (peritoneal), heart (pericardial) or testes (testicular). Patients with the epithelial tumor cell type live about six months longer than those with biphasic or sarcomatoid cell types. Epithelial cells respond better than others to aggressive treatment.

“The epithelial type does tend to be more favorable,” mesothelioma specialist Dr. Andrea Wolf of Mount Sinai Hospital told The Mesothelioma Center at Asbestos.com. “It does tend to respond to chemotherapy a little more easily.”

What Causes Epithelial Mesothelioma?

The primary risk factor and cause of epithelioid mesothelioma is the same as other cell types of mesothelioma: asbestos exposure. Inhalation or ingestion of asbestos fibers causes tissue inflammation and DNA damage, leading to cancer development decades later.

Most people diagnosed with epithelioid mesothelioma worked with asbestos products long before their diagnosis. All mesothelioma cell types have a latency period of 20 to 60 years. The first symptoms may not show up for decades after the initial asbestos exposure. 

The Patient Advocates at The Mesothelioma Center say many newly diagnosed patients who call to ask questions about their mesothelioma diagnosis typically do not know their cell type. It’s important to ask your doctor about cell type because it will help you understand your symptoms, treatment and prognosis.

Epithelioid Mesothelioma Symptoms

Epithelioid mesothelioma symptoms often include cough, shortness of breath and lack of appetite. As the disease progresses, more severe symptoms may surface. Many symptoms depend on tumor location and size.

Mesothelioma symptoms are the same, no matter the cell type. A person with epithelial tumors will have symptoms similar to those with the sarcomatoid type. However, the cell type affects which treatments are most helpful. Talk to your doctor if you experience any of these symptoms.

How Is Epithelioid Mesothelioma Diagnosed?

A tissue biopsy is the only way to diagnose epithelial mesothelioma. This procedure samples the lung tissue to confirm the cell type under a microscope. Epithelial mesothelioma cells clump together in groups and do not tend to travel. These cells are less likely to spread to other areas of the body.

“Epithelial subtype mesothelioma describes the type of cells the pathologist is seeing under the microscope when they look at a patient’s tumor,” Dr. Andrea Wolf noted. 

Epithelial mesothelioma cells can take on a variety of shapes and sizes. These include cuboid (square), columnar (long) or squamous (flat). The cells also carry DNA within a visible nucleus. 

Understanding Your Pathology Report

After a biopsy, the pathologist will create a report for your physician. This report includes cell distribution and a final diagnosis. The pathology report describes the types of mesothelioma cells found in a patient’s tumors. The cell type informs your doctor how your cancer might progress. It also determines which treatment options may be best.

“When I first speak with a patient, I ask about their diagnosis and cell type,” Patient Advocate Danielle DiPietro noted. “If they say they don’t know, I explain how to find it on their pathology report. I also explain the three cell types and their meaning for their mesothelioma journey.”

Epithelial Cell Subtypes

Pathologists use chemical stains to reveal immunohistochemical markers and identify subtypes. If you have a specific subtype, it could influence your treatment options or mesothelioma prognosis. Rare subtypes could lead to a misdiagnosis. Some epithelioid cell subtypes, such as adenomatoid, are associated with better survival. Epithelial subtypes include:

“When I speak with a patient who is hesitant to have a biopsy, which is rare, I explain that knowing the cell type is imperative when assessing treatment options,” DiPietro said.

Talk to your mesothelioma doctor about your cell type, cancer stage and tumor grade (speed of tumor growth). Ask how these factors affect your treatment plan and prognosis.

What Is the Survival Rate for Epithelial Mesothelioma?

The 5-year survival rate for epithelioid pleural mesothelioma is 12%. A peritoneal mesothelioma study showed a median survival of 55 months for patients with epithelioid cells. By comparison, patients with sarcomatoid or biphasic cells had a median survival of seven to 13 months.

The survival rate for epithelial patients is overall significantly longer. Epithelial cell type is the best mesothelioma cell type to have. This patient will have more options, such as surgery, and is more likely to respond to treatment.

Karen Selby

Patient Advocate

Epithelioid patients live 200 days longer on average than patients with other cell types. The life expectancy of epithelial malignant mesothelioma patients is 18 months. The overall survival of all cell types drops when the disease metastasizes or spreads.

How Is Epithelioid Mesothelioma Treated?

Doctors treat early-stage epithelioid mesothelioma aggressively with surgery, chemotherapy and radiation therapy. Late-stage cases respond better to palliative care with immunotherapy, chemotherapy and Tumor Treating Fields therapy. A combination of approaches is often the most effective method.

Your treatment will depend on the cancer stage, tumor extent and overall health. Of the three cell types, epithelial mesothelioma responds best to treatment. 

Consider a second opinion at a top cancer center. The specialists at these centers have the experience to diagnose and treat epithelioid mesothelioma effectively. They can offer clinical trials and multidisciplinary treatment to control the disease with different therapies.

Common Questions About Epithelioid Mesothelioma

Where can I get treatment for epithelial cell mesothelioma?

Look for mesothelioma specialists with years of experience treating pleural and peritoneal mesothelioma. Most oncologists need to be trained to treat epithelioid mesothelioma. Our Patient Advocates can help you find a top doctor who treats epithelial mesothelioma.

Can epithelioid mesothelioma be prevented?

Asbestos exposure is the primary cause of mesothelioma. Avoiding it is the best way to prevent mesothelioma. If you have a history of asbestos exposure, talk to your doctor about cancer screenings, which may aid in an early diagnosis.

Is epithelioid mesothelioma curable?

Unfortunately, epithelioid mesothelioma has no cure. But patients with the epithelioid cell type have the most mesothelioma treatment options. This cell type responds the best to all forms of treatment.

Is there any ongoing research on epithelioid mesothelioma?

Researchers are constantly looking for mesothelioma patients with the epithelioid cell type for clinical trials. They seek out these participants because epithelioid is the disease’s most common cell type. Studying epithelioid patients lets researchers know how a drug or therapy will affect most patients diagnosed with mesothelioma.

How can epithelial cells turn into mesothelioma?

Epithelial cells line the airways and are constantly exposed to substances from the air you breathe. One of the main causes of mesothelioma is asbestos exposure. When you inhale asbestos fibers, they can become trapped in the lungs and induce inflammation. Long-term inflammation can lead to mutations in epithelial cells, eventually giving rise to cancer.