Myeloid sarcoma (MS), also known as chloroma (owing to its green color attributed to the enzyme myeloperoxidase), is a pathologic diagnosis for an extramedullary proliferation of blasts of one or more of the myeloid lineages that disrupt the normal architecture of the tissue in which it is found. Myeloid sarcoma is an extramedullary tumor composed of immature myeloid cells that efface the underlying tissue architecture. It is usually associated with acute myelogenous leukemia, but can be associated with myeloproliferative neoplasms, myelodysplastic disorders, or myeloproliferative/ myelodysplastic syndromes. Most people diagnosed with a soft tissue sarcoma are cured by surgery alone, if the tumor is low-grade; that means it is not likely to spread to other parts of the body. More aggressive sarcomas are harder to treat successfully.