Sarcoma

A sarcoma (from the Greek sarx (σάρκα) meaning "flesh") is a cancer that arises from transformed cells of mesenchymal origin. Thus, malignant tumors made of cancerous bone, cartilage, fat, muscle, vascular, or hematopoietic tissues are, by definition, considered sarcomas. This is in contrast to a malignant tumor originating from epithelial cells, which are termed carcinoma. Sarcomas are quite rare. Common malignancies, such as breast, colon, and lung cancer, are almost always carcinoma.