Multiple Myeloma

Etiology

  • Proliferation monoclonal plasma cells that make monoclonal protein
  • Multiple myeloma accounts for 1% of all cancers in US, 10% of all hematologic cancers in US

Risk Factors

  • Median age 66
  • Monoclonal Gammopathy Undetermined Significance (MGUS)--> monoclonal protein elevation < 3g/dl and no other target organ dysfxn (sometimes peripheral neuropathy or hypercoag); progresses to myeloma ~1%/y
  • Smoldering Myeloma--> monoclonal protein > 3g/dl, 10% plasma cells in BM, but no target organ dysfxn; progresses to myeloma 10%/y

Symptoms

  • CRAB pneumonic defines target organ dysfxn associated w/myeloma: hyperCalcemia (e.g. polyuria, confusion, constipation, abdominal pain), Renal dysfunction, Anemia (fatigue, sob, wt loss, doe), Bone involvement (painful lytic lesions)
  • Sometimes progressive motor/sensory peripheral neuropathy--> weakness, numbness, pain
  • Sometimes recurrent infections
  • Eye symptoms/blurred vision, confusion--> concerning for hyperviscocity - usually from mono-clonal IgM spike (Waldenstroms, w/large pentamers--> sludging), though can be IgA or IgG

Physical Exam Findings

  • Edema
  • Sometimes areas of focal bone pain
  • Sometimes confusion
  • Sometimes decreased vision

Tests