Myeloma is a cancer. Myeloma is a malignant tumor originating from plasma cells in the bone marrow and can be solitary or multiple. Multiple myeloma synthesizes immunoglobulin-secreting plasma cells that become malignant and multiply in large numbers, causing peripheral soft tissue involvement as the disease worsens. The cause of myeloma is unknown and is generally related to chronic irritation, ionizing radiation and genetic factors. Often tuberculosis, as well as chronic osteomyelitis and autoimmune diseases, induce an increased incidence of myeloma. Myeloma can be controlled with medications such as thalidomide or prednisone, and can be treated with hematopoietic stem cell transplantation when available.