What is the difference between sarcomatoid mesothelioma and sarcoma?

Different tumors: , Sarcomatoid mesothelioma is the least common of the disease’s three main histological cell types: epithelioid, sarcomatoid and biphasic. This type has been called sarcomatous, diffuse malignant fibrous and spindled mesothelioma. It accounts for 7 to 20 percent of all mesotheliomas . The cells appear elongated,and spindle-shaped.The Sarcomas in general are a broad spectrum of malignant tumors arising in supportive tissue such as muscle, bone, nerve and blood vessel tissue. They are unrelated to the mesotheliomas