The early stages of myeloma may have no overt symptoms, but symptomatic disease develops as tumor mass increases and excess protein is produced by the tumor cells. The symptoms vary from patient to patient but often include bone pain and fatigue. Frequent infections are also common because the immune system becomes compromised when malignant myeloma cells crowd out healthy white blood cells.
Seventy-five percent of patients present with bone pain, frequently in the back, long bones, pelvis, and skull. Lower back pain is a common complaint.
Malignant plasma cells release cytokines, osteoclast-stimulating factors that cause calcium to be leached from bones. This can result in lytic lesions, or holes that cause severe pain and bone weakness. The risk of fractures increases and compression fractures of the vertebrae are common. Multiple compression fractures may culminate in kyphosis, a forward curving of the spine, which results in loss of height. The cytokines also may prevent death of myeloma cells, contributing to the problems that are caused by excess myeloma plasma cells.
Fifty percent of patients have radiologically detectable myeloma-related skeletal lesions at diagnosis. The Myeloma Institute has found that magnetic resonance imaging (MRI) is more effective than conventional x-rays at demonstrating the existence and exact location of bone tumors and lesions. MRI is a standard diagnostic tool for patients being evaluated at the Myeloma Institute.
Characterized by low red blood cell count due to inhibition of normal red blood cell production, anemia occurs in almost all patients with multiple myeloma. Anemia can cause weakness, dizziness, shortness of breath, and fatigue.
Anemia can result from:
Heavy infiltration of malignant cells in the bone marrow; the malignant cells crowd out healthy cells, including red cells, which carry oxygen throughout the body.
Renal impairment that leads to deficient production of erythropoietin, a hormone produced by the kidneys that stimulates red blood cell production.
Hyperviscosity refers to an increase in the viscosity, or resistance to flow, of the blood. It occurs as a result of high levels of protein in the blood, specifically M proteins that attach themselves to platelets and interfere with platelet function. Hyperviscosity can result in: