Myeloma is a condition in which plasma cells, the cells in bone marrow that produce antibodies, become cancerous. Myeloma is sometimes referred to as plasma cell dyscrasia or plasma cell myeloma, and most commonly as multiple myeloma (MM). Multiple myeloma is the most common form of myeloma found in patients, and it is so named because it involves multiple sites in the body. The myeloma cells begin to grow at an uncontrollable rate and develop into tumors at numerous sites. However, a small percentage of patients develop myeloma cells outside the bone marrow, and others have solitary myeloma, meaning the disease affects only a single area.

Myeloma often presents with bone pain, primarily in the spine and ribs, though other locations are also commonly affected. The pain typically worsens with movement. Other common symptoms include chronic or acute infection, anemia, and kidney failure. However, myeloma is so varied in its formation and development that the symptoms of myeloma can be equally varied.

Diagnosis of myeloma typically follows a physical examination and recording of health history, combined with blood and urine laboratory tests. Elevated paraprotein and calcium levels are laboratory indicators. If myeloma is suspected, further diagnostics including a skeletal survey or computed tomography (CT) scan, along with a bone marrow biopsy. The method of diagnosis is dependent on the treating physician.

The prognosis for myeloma is typically not good. Though there is currently no cure for myeloma, treatment is an option. Treatment revolves around containment of the disease and suppression of both the symptoms and disease progression.

The underlying symptoms of myeloma, including anemia and renal failure, if present, must be treated first. Steroids and chemotherapy are standard treatment options for myeloma. In some cases, stem cell transplant is a suggested treatment.

Most patients who have been treated for myeloma and achieve clinical remission relapse at some point. According to the International Staging System (ISS) for myeloma, the median survival prognosis for stage 1 myeloma is 62 months, stage 2 is 49 months, and stage 3 is 29 months.