The Maune Raichle Law Firm

Mesothelioma Cells

Cancers of the mesothelium can take 3 basic forms which relate to the fact that the mesothelioma afflicts 2 distinct cell types, epithelial and connective tissue. The two distinct cancerous cell types of mesothelioma are epithelioid and sarcomatoid mesotheliomas. The difference between the two cell types can be important in treatment as different therapies are effective on each type of cancer cell. About a third of mesotheliomas are biphasic, composed of both cell types, and present themselves as either a tumor with a mixture of both types of cancer cells intermixed or as 2 distinct sets of cells within a tumor.

Epithelioid mesothelioma is by far the most common form of mesothelioma cancer. Its tumors are composed exclusively of epithelioid, skin cells which tend to be uniform, with a tubular pattern. The epithelioid mesothelioma cells also have a clearly defined nucleus, and individual cells are cubic or in the shape of a multisided box. The cells often appear very similar to other cancer cells so examination under high magnification with specialized stains is often necessary to differentiate them from cells of other cancers. Often, the only other way to differentiate epithelioid mesothelioma cells from cells of other cancers is through an analysis of protein markers.

Sarcomatoid mesothelioma is quite rare, accounting for about 15% of all mesothelioma cases. They are typically an irregular oval shape with no visible nucleus under simple magnification. The cells of sarcomatoid mesothelioma resemble those of other sarcomas and because of this similarity it can often be difficult for doctors to diagnose sarcomatoid mesothelioma, which often results in misdiagnosis. Like epithelioid mesotheliomas, sarcomatoid mesothelioma can be differentiated from other cancers by an analysis of protein markers.