Small round blue cell tumors receive this name because of their appearance under the microscope, as they are viewed as small, round, blue-stained, undifferentiated cells. Sarcomas consist of malignant cells that usually produce a substance called a matrix. Small round blue cell sarcomas consist of all cells and no matrix. They do not produce any additional substances or tissues. Small round blue cell tumors sarcomas are malignant (cancerous) and are more common in children. Examples include, Ewing’s Sarcoma/primitive neuroectodermal tumor, rhabdomyosarcoma, desmoplastic round cell tumor, small cell lymphoma, and neuroblastoma. They more commonly come from the bone but can also develop from the soft tissues. Treatment and prognosis for these tumors are determined after a diagnosis is confirmed and after a consultation with an orthopedic oncologist. They are often treated with chemotherapy and surgery. They may be associated with genetic alterations and chromosomal translocations in the tumor. A type of benign small round blue cell tumor is called eosinophilic granuloma.