Smoldering Multiple Myeloma

Individuals with smoldering myeloma (asymptomatic myeloma) have a slightly increased level of M protein and a slightly increased number of plasma cells in the bone marrow. Smoldering myeloma is characterized by a lack of multiple myeloma symptoms. Patients may have mild anemia and/or a few bone lesions, but they do not have renal failure and frequent infection, which characterize the active form of the disease. Instead, myeloma is static and may not progress for months or years. Asymptomatic multiple myeloma includes both smoldering multiple myeloma and indolent multiple myeloma.

The characteristics of smoldering multiple myeloma include:

  • Serum M protein level of ≥ 3 g/dL and/or ≥ 10% plasma cells in bone marrow
  • Absence of anemia (although slight anemia may occur), renal failure, hypercalcemia, and osteolytic lesions
  • The characteristics of indolent multiple myeloma include
  • Level of M protein in the serum and/or urine, ≥ 3 g/dL and stable over time
  • Percentage of plasma cells in bone marrow, > 30%
  • Mild anemia or a few small osteolytic lesions

Lack of symptoms

Individuals with asymptomatic multiple myeloma have “close follow-up” (also called observation), with visits to the physician and/or testing approximately every 3 months. Treatment with bisphosphonates is started for individuals who have osteolytic lesions, osteoporosis, or osteopenia. Treatment directed at myeloma is started once the disease has progressed to symptomatic myeloma. Participation in a clinical trial is also encouraged.