Epithelial Mesothelioma

Epithelial mesothelioma cells have a definite structure with visible nuclei. This is the most common variant of this type of mesothelioma cancer, accounting for about 60 percent of all cases. This type of mesothelioma develops when malignant cells develop on any of the mesothelial linings. When examined under a microscope, these mesothelioma cell types are of a uniform size and shape, and resemble normal, healthy epithelial cells.
Epithelial mesothelioma cells also bear a strong resemblance to adenocarcinoma cells, which are also associated with lung tissue. Patients who have been diagnosed with adenocarcinoma should also be examined for mesothelioma diagnosis as well.

Variants

Papillary mesothelioma is an example of epithelial mesothelioma; other variants include any of the following:

• Signet Ring
• Single File
• Adenoid Cystic
• Glandular
• Tubulopapillary
• Histiocytoid
• Microcystic
• Macrocystic
• Glomeruloid

• Diffuse - NOS
• Small Cell
• Deciduoid
• Pleomorphic
• In Situ
• Mucin Positive
• Well-Differentiated Papillary
• Gaucher Cell-Like

What differentiates these various types are the shape, size and formation of the cells. This can determine what course of mesothelioma treatment is appropriate for the patient's situations.

Epithelial Mesothelioma and Asbestos

Once asbestos fibers are inhaled, they become lodged in the lung tissue, where they remain indefinitely. Mesothelioma is associated with hard, crystalline amphibole asbestos, which consists of hard, needle-like fibers that literally bore through lung tissue over time, causing chronic inflammation that ultimately results in malignancy. The mesothelioma latency period, can be anywhere from five to seventy-five years. Mesothelioma symptoms are similar to those of other respiratory illnesses, which is why a mesothelioma diagnosis has historically been so difficult to make.

Sources

Dodson, R. and Hammar, S. Asbestos: Risk Assessment, Epidemiology, and Health Effects. (Boca Raton: Taylor & Francis, 2006).
Pass, I., Vogelzang, N., Carbone, M. Malignant Mesothelioma: Advances in Pathogenesis, Diagnosis, and Transitional Therapies. (New York: Springer, 2005)