Multiple myeloma, also known as malignant plasmacytoma or plasma cell myeloma, is a disseminated malignant neoplasia of marrow plasma cells that infiltrates bone to produce osteolytic lesions throughout the skeleton (flat bones, vertebrae, skull, pelvis, and ribs). It's a rare disease with only three new cases occurring per 100,000 people a year.
Multiple myeloma most commonly affects men over age 40.
Prognosis is usually poor because diagnosis is typically made after the disease has already infiltrated the vertebrae, pelvis, skull, ribs, clavicles, and sternum. By then, skeletal destruction is widespread and vertebral collapse is imminent. Without treatment, about half of all patients die within 6 months of diagnosis. Early diagnosis and treatment prolong the lives of many patients by 3 to 5 years. Death usually follows complications, such as infection, renal failure, hematologic imbalance, fractures, hypercalcemia, hyperuricemia, or dehydration.
Primary cause unknown
· Genetic factors
· Autoimmune diseases or allergies
· Environmental toxins
· Chemicals in agricultural products or added during food processing
Plasma cells are normal leukocytes that secrete immunoglobulins. When plasma cells become malignant, they reproduce uncontrollably and create many abnormal immunoglobulins. During this process, they invade the bone marrow, then the bone matrix, causing osteolytic lesions of the bone. Myeloma cells then proliferate outside of the bone marrow in all lymphatic tissues where plasma cells are normally present. Because plasma cells exist in virtually all body organs, all body systems may be affected by this proliferation and abnormal immunoglobulin production. The severity of renal failure correlates with the amount of immunoglobulin protein found in the urine. Infiltration and precipitation of immunoglobulin light chains (Bence-Jones protein) in the distal tubules causes myeloma nephrosis.
Signs and symptoms
· Severe, constant back and rib pain that increases with exercise and may be worse at night
· Arthritic symptoms—achy pain; swollen, tender joints
· Fever, malaise
· Evidence of peripheral neuropathy (such as paresthesia)
· Evidence of diffuse osteoporosis and pathologic fractures
In advanced disease
· Acute symptoms of vertebral compression; loss of body height—5″ (12.5 cm) or more
· Thoracic deformities (ballooning)
· Weight loss
· Severe, recurrent infection, such as pneumonia, may follow damage to nerves associated with respiratory function
Diagnostic test results
· Complete blood count shows moderate to severe anemia; differential may show 40% to 50% lymphocytes but seldom more than 3% plasma cells.
· Differential smear reveals rouleaux formation from elevated erythrocyte sedimentation rate.
· Urine studies reveal Bence Jones protein and hypercalciuria.
· Bone marrow aspiration detects myelomatous cells (abnormal number of immature plasma cells).
· Serum electrophoresis shows elevated globulin spike that's electrophoretically and immunologically abnormal.
· Bone X-rays in early stages reveal diffuse osteoporosis; in later stages, they show multiple sharply circumscribed osteolytic lesions, particularly in the skull, pelvis, and spine.
· Chemotherapy to suppress plasma cell growth and control pain
· Autologous hematopoietic blood cell transfusion
· Autologous bone marrow transplantation
· Adjuvant local radiation
· Melphalan-prednisone combination in high intermittent or low continuous daily doses
· Analgesics for pain
BONE MARROW ASPIRATE IN MULTIPLE MYELOMA