Sarcomatoid Mesothelioma: Things You Should Know

Sarcomatoid mesothelioma is the least common form of mesothelioma.  It is a type of cancer that is caused by asbestos exposure.  It accounts for only about 10 to 20 percent of the mesothelioma cancer cells.  Sarcomatoid cells appear as an irregularly shaped oval.  Its nucleus is not very visible under an electron microscope, unlike the nuclei of epithelioid mesothelioma cancer cells.  It is sometimes confused with sarcomatoid carcinoma and other sarcoma because the irregular oval shape is common among cancer cells.   

It is the most serious form of mesothelioma cancer.  Also, it is hard to diagnose and it rarely responds to any type of therapy or treatment.  As with all forms of malignant mesothelioma, it is aggressive and fatal.  Usually, just within 6 months of diagnosis, death occurs. 

There are three forms of malignant mesothelioma cancer.  It is divided into three main categories and is dependent on the part of the mesothelium that it attacks.  There’s the peritoneal mesothelioma, which occurs in the peritoneum or abdomen, pleural mesothelioma which occurs in the lining of the lungs or chest cavity, and pericardial mesothelioma which occurs in the lining of the heart.  Mesothelioma sarcomatoid is one of the three main sub types of mesothelioma that are grouped based on how the cells look under the microscope. 

Diagnosis

It is diagnosed by a histopathogist.  The histopathologist uses a high powered microscope to examine a section of the suspect tissue.  Through a biopsy, a section of the tissue is then removed using this type of diagnostic surgery.  Sometimes, it is confused with other sarcomas since it has a similar cellular structure and originates in the same areas of the body.

What is Sarcoma?

Sarcoma is a form of cancer.  It originates in the bone, cartilage, muscle, fat, or other supportive tissues of the body. 

Sarcoma vs. Sarcomatoid Mesothelioma

It is sometimes confused with high-grade sarcoma.  Sarcoma arises in the supportive tissues.  It can be difficult to differentiate if the sarcoma spreads to the pleural surface. 

Also, they have a similar appearance.  This is the case when observed under a high powered microscope and the staining of the tumor cells.  In these cases, the pathologist should be extra careful in comparing the staining of the cells and appearance, as well as the overall appearance (localized vs diffuse pleural-based mass) and regularity of the tumor when making a definitive diagnosis. 

Comparison with Sarcomatoid Carcinoma

It can also be confused with sarcomatoid carcinoma.  Most often, pulmonary sarcomatoid carcinoma is confused with mesothelioma sarcomatoid.  Similar to it, sarcomatoid carcinomas of the lung are four times more likely in men than in women.  There is a strong connection with smoking.  Both conditions also share certain symptoms including pleural effusions, chest pain and respiratory difficulty. 

Because of these similarities, be extra careful.  If you or a loved one has been diagnosed with pulmonary sarcomatoid carcinoma or high-grade sarcoma, and have had previous asbestos exposure, it might be a wise idea to seek a second thorough examination from an oncologist who specializes in mesothelioma, and specifically sarcomatoid mesothelioma.