MULTIPLE MYELOMA

Clinical

• Average age is 60-70
• Men much more common than women
• Most have an elevated serum protein with 80-90% in the globulin fraction, especially IgG
• Bence-Jones protein in 40-60% of patients (light chains)

X-ray findings

• Osteoporosis is most common skeletal abnormality in this disease
• Lesions are usually multiple and found in vertebrae, ribs, skull, pelvis, and femur
• Over 50% of solitary lesions are found in vertebrae
• Mandible involved in 1/3 of patients with diffuse involvement
• Widespread lucencies in bone
  • Discrete, “punched-out” lesions
  • Uniform in size
• Distinctive to MM are the lucent, elliptical, subcortical shadows, especially in long bones=endosteal scalloping
  • Due to buttressing since MM is usually a slower process than mets
• In spine, MM destroys body and spares pedicle

DDX: mets and disuse osteoporosis

• MM is more widespread
• More discrete holes in MM
• Large foci of coalescence more often due to mets
• Severe disuse osteoporosis may simulate bone changes of MM

Sclerosis is usually seen only with treatment or fracture

• Bone scans may typically be negative and many hot  areas on scan may be healing fractures

Most believe that almost all patients with a solitary plasmacytoma will develop multiple myeloma

• Solitary plasmacytoma produces “soap-bubbly” expansile, septated lesion, when characteristic

 

Multiple myeloma . The pelvis contains numerous lytic lesions without reactive sclerosis which
have an almost "soap-bubbly" appearance in the ischia. There are also lytic lesions in
both proximal femora.
Other examples of Multiple Myeloma (Click on each to enlarge)

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