Sarcoma mesothelioma accounts for only about 10 to 15 percent of the mesothelioma cancer cells and it is the least common form of mesothelioma. Sarcomatoid cells are typically oval shaped, but more irregular. The nucleus of sarcomatoid cells is not as clearly visible under an electron microscope as the nuclei of epithelioid mesothelioma cancer cells. Because the irregular oval shape is a common among cancer cells, sarcoma mesothelioma can be confused with sarcomatoid carcinoma and with sarcoma.

sarcoma mesothelioma Versus Sarcomatoid Carcinoma

sarcoma mesothelioma is often confused with a wide variety of other types of cancer because of the sarcomatoid appearance, including sarcomatoid carcinoma. Although sarcomatoid cancer appears in other parts of the body, such as the kidney, it is relatively rare in the lungs. No more than 1.3 percent of lung carcinomas are of the sarcomatoid type.

Pulmonary sarcomatoid carcinoma is the type most often confused with sarcoma mesothelioma. Similar to sarcoma mesothelioma, sarcomatoid carcinomas of the lung are much more common in men (four times more likely than in women) and there is a strong association with smoking. Pulmonary sarcomatoid carcinoma and sarcoma mesothelioma also share certain symptoms, such as chest pain, pleural effusions and respiratory difficulty.

sarcoma mesothelioma Versus Sarcoma

sarcoma mesothelioma also can be confused with high-grade sarcoma. While carcinoma affects the epithelium, sarcoma arises in the supportive tissue (bone, cartilage, fat or muscle). If the sarcoma spreads to the pleural surface, it can be difficult to differentiate from sarcoma mesothelioma.