Paraprotein Levels

Good Evening Jane;

Your answers are in the following article:

Diagnostic criteria

In 2003, the International Myeloma Working Group[1] agreed on diagnostic criteria for symptomatic myeloma, asymptomatic myeloma and MGUS (monoclonal gammopathy of undetermined significance):

• Symptomatic myeloma:
  1. Clonal plasma cells >10% on bone marrow biopsy or (in any quantity) in a biopsy from other tissues (plasmacytoma)
  2. A monoclonal protein (paraprotein) in either serum or urine
  3. Evidence of end-organ damage (related organ or tissue impairment, ROTI):
     • Hypercalcemia (corrected calcium >2.75 mmol/L)
     • Renal insufficiency attributable to myeloma
     • Anemia (hemoglobin <10 g/dL)
     • Bone lesions (lytic lesions or osteoporosis with compression fractures)
     • Frequent severe infections (>2 a year)
     • Amyloidosis of other organs
     • Hyperviscosity syndrome
• Asymptomatic myeloma:
  1. Serum paraprotein >30 g/L AND/OR
  2. Clonal plasma cells >10% on bone marrow biopsy AND
  3. NO myeloma-related organ or tissue impairment
• Monoclonal gammopathy of undetermined significance (MGUS):
  1. Serum paraprotein <30 g/L AND
  2. Clonal plasma cells <10% on bone marrow biopsy AND
  3. NO myeloma-related organ or tissue impairment

Related conditions include solitary plasmacytoma (a single tumor of plasma cells, typically treated with irradiation), plasma cell dyscrasia (where only the antibodies produce symptoms, e.g. AL amyloidosis), and POEMS syndrome (peripheral neuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, skin changes).

The International Staging System (ISS) for myeloma was published by the International Myeloma Working Group in 2005:[4]

• Stage I: β2-microglobulin (β2M) < 3.5 mg/L, albumin >= 3.5 g/dL
• Stage II: β2M < 3.5 and albumin < 3.5; or β2M >= 3.5 and < 5.5
• Stage III: β2M >= 5.5

First published in 1975, the Durie-Salmon staging system [5] is still in use, but has largely been superseded by the simpler ISS:

• stage 1: all of
  • Hb > 10g/dL
  • normal calcium
  • Skeletal survey: normal or single plasmacytoma or osteoporosis
  • Serum paraprotein level < 5 g/dL if IgG, < 3 g/dL if IgA
  • Urinary light chain excretion < 4 g/24h
• stage 2: fulfilling the criteria of neither 1 nor 3
• stage 3: one or more of
  • Hb < 8.5g/dL
  • high calcium > 12mg/dL
  • Skeletal survey: 3 or more lytic bone lesions
  • Serum paraprotein >7g/dL if IgG, > 5 g/dL if IgA
  • Urinary light chain excretion > 12g/24h

Stages 1, 2 and 3 of the Durie-Salmon staging system can be divided into A or B depending on serum creatinine:

• A: serum creatinine < 2mg/dL (< 177 umol/L)
• B: serum creatinine > 2mg/dL (> 177 umol/L)

Take care;

Kevin