What is Epithelioid Mesothelioma?

What Is the Function of Epithelioid Cells?

Epithelial mesothelioma occurs when malignant (mutated cancer cells) epithelial cells spread along the lining of the lung airways. Mesothelioma, a rare form of cancer caused by asbestos exposure, occurs in the tissues throughout the chest cavity, abdomen, thoracic cavity, or testes. The original site of the mesothelioma tumor, caused by a gene mutation from asbestos, contains either epithelioid cells, sarcomatoid cells, or a combination of both.

Mesothelioma arising from epithelial cell type comprises between 50% and 70% of mesothelioma cases. A small fraction (about 15%) of mesothelioma patients can have both epithelial and sarcomatoid cells, known as biphasic mesothelioma. Cancerous epithelioid cells commonly develop in the lining of the bronchi, the large tubes that connect to your windpipe and direct the air you breathe. Epithelioid cells clump easily, creating tumors, though they spread slowly.

Research suggests that mesothelioma cell types have prognostic and predictive implications. Physicians, specifically cancer doctors called oncologists, use the mesothelioma cell type as a significant prognostic factor. Primary sarcomatoid cell type is associated with longer life expectancies among mesothelioma patients due to its nature, which is slower than epithelioid-type cells. When treated with the top treatment options, patients living with epithelial mesothelioma can live an average of nearly two years longer than without treatment.

Symptoms of Epithelioid Cell Mesothelioma

Epithelial cell mesothelioma symptoms are the same as other cell types. Thus, a person with sarcomatoid cell mesothelioma may experience the same symptoms as someone with epithelial cell mesothelioma. The signs and symptoms of epithelial cell mesothelioma include:

• Anemia
• Coughing up blood
• Fatigue
• Fever
• Hoarseness
• Lack of appetite/feeling full without eating
• Low blood oxygen levels
• Nausea
• Night sweats
• Persistent dry cough
• Shortness of breath
• Weight loss

Epithelial Mesothelioma Diagnosis

If you are diagnosed with mesothelioma, you may undergo several tests to define the primary cell type. Most patients undergo imaging scans first to spot tumors, followed by a tissue biopsy (where tissue is removed and examined under a microscope) that may find epithelial cells. Additional lab tests can be done to detect other characteristics of the particular cell type.

A pathologist, a physician who primarily evaluates tissues, may be involved in your care after a mesothelioma diagnosis. They can distinguish between epithelial and other mesothelioma cells by administering specialized cancer-fighting antibodies and evaluating how your body reacts via blood testing. The antibodies find and bind to specific proteins on the surface of malignant epithelial cells.

Malignant epithelial cells can appear square, long, or flat. Doctors sometimes find difficulty distinguishing epithelial mesothelioma from a more common condition called adenocarcinoma. Confirming the presence of mesothelioma cells often requires modern diagnostic techniques to take a tissue sample.

Due to the rarity of the disease, most doctors have never diagnosed mesothelioma. Certain multidisciplinary mesothelioma doctors, including surgeons, radiologists, or oncologists, specialize in diagnosing and treating the disease. They have experience and can identify rare characteristics of mesothelioma, including cell subtypes.

Related: Top 5 Doctors Specializing in Mesothelioma Treatment

Epithelial Mesothelioma Cell Subtypes

Epithelioid cells vary in characteristics, distribution, and progression. To calculate the best treatment option for each unique mesothelioma diagnosis, a pathologist determines the subtype of epithelioid mesothelioma from various options. We can classify epithelioid mesothelioma even further by distinguishing the cell subtype.

• Tubulopapillary: The most common subtype of epithelioid mesothelioma cells is tubulopapillary, which is often found in the lining of the lungs, called the pleura.
• Glandular: Malignant glandular cells also develop in the pleura but are distinguished by their glandular pattern.
• Adenomatoid: A small percentage of pleural epithelioid mesothelioma occurrences contain malignant adenomatoid cells, which appear flat and cube-like.
• Solid: Patterns of the solid subtype of epithelioid mesothelioma appear as poorly distinguished accumulations of round and straight-sided cells.
• Deciduoid: Deciduoid mesothelioma is a rare subtype of epithelial mesothelioma involving large malignant cells appearing to have round or sharp borders.
• Well-Differentiated Papillary Mesothelioma (WDPM): WDPM is a rare subtype of epithelioid mesothelioma occurring mostly in the peritoneum of women.
• Small Cell: Small cell mesothelioma is an extremely rare cell subtype and is often misdiagnosed as small cell lung cancer but is treated with standard therapies.

Epithelial Mesothelioma Treatment Options

Treatment for epithelial mesothelioma varies based on where the cells originate and how far they spread. Epithelioid mesothelioma cells typically originate in the lining of organs, while sarcomatoid cells derive from bones or soft tissues. Mesothelioma patients experience better survival rates when physically able to undergo multiple treatments, including radiation and surgery. Tumors containing epithelioid cells spread slower than sarcomatoid cells and may be easier to access and treat.

Epithelial mesothelioma treatment options often include a combination of immunotherapy, chemotherapy, and surgery if possible. When mesothelioma patients are physically able to undergo surgery, they may receive chemotherapy or radiation to suppress any remaining cells following the procedure. Modern treatments can be accessed at some of the top mesothelioma medical centers around the United States.

One study of patients with epithelial mesothelioma found the median survival without treatment was just over 10 months. Meanwhile, patients who underwent chemotherapy alone survived a little over 15 months. Patients who underwent surgery and received chemotherapy and/or radiation survived over 21 months.

Treatment for the rare disease requires the expertise of a team of mesothelioma specialists. Mesothelioma specialists have experience with the diagnostic and treatment process, and each serves a specific patient need. Specialists in mesothelioma care may include a combined effort of medical, radiation, and surgical oncologists, radiologists, pathologists, nurses, pulmonologists, and many more.