Serum FLC Case Studies Fiona Kilvington Binding Site Ltd

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Serum FLC Case StudiesFiona
KilvingtonBinding Site Ltd
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Screening for monoclonal gammopathies

• sFLC CZE
• 9 additional B-cell disorders identified from
  1003 consecutive unknown samples
• Bakshi et al. Am J Clin Path 2005 124 214-218
• sFLC SPE
• 16 additional B-cell disorders identified from
  312 samples
• Abadie Bankson Ann Clin Lab Sci 2006 36
  157-162
• 8 additional monoclonal gammopathies identified
  from 923 unknown samples
• Hill et al. Clin Chem 2006 52 1743-1748

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Screening using sFLC and SPE

• 653 consecutive unknown serum samples
• 597/653 normal by SPE and FLC
• 17/653 clear band on SPE and abnormal FLC
• 18/653 no band on SPE/IFE but abnormal FLC ratio

Courtesy of S. Basu and T. Lovatt
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Normal SPE/Abnormal FLC

• 12/18 Lymphoproliferative disorders
• 1 IgD Myeloma
• 1 IgA Myeloma/MGUS
• 6 CLL (1 undiagnosed at the time of screening)
• 4 FLC-MGUS
• 6/18 no LPD

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Case 1 IgD Myeloma

• 74 yr old female
• Lab Results
• IgG 11.3, IgA 2.39, IgM 0.23 g/L
• Hb 10.9 g/dL
• B2M 3.3 mg/L (lt2.4)
• CRP 60 mg/L
• ESR 42ml/hr (lt12)

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Case 1 IgD Myeloma
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Case 1

• SPE - no obvious paraprotein
• Insufficient evidence to initiate IFE
• Serum Free Light Chain Analysis
• Kappa 27.8mg/L
• Lambda 868mg/L
• Kappa/Lambda Ratio 0.003

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Case 1 IgD Myeloma

• IFE demonstrated the presence of an IgD Lambda
  paraprotein
• Patient referred to Haematologist
• Follow-up Investigations confirmed myeloma
• Patient refused follow up

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Case 2 IgA Myeloma

• 73 yr old female
• Seen by GP with mobility issues
• Lab Results
• IgG 10.3, IgA 4.29, IgM 1.1 (g/L)
• Hb 11.2 g/dL
• CRP 23 mg/L

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Case 2 IgA Paraprotein
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Case 2

• SPE - no obvious paraprotein
• Insufficient evidence to initiate IFE
• Serum Free Light Chain Analysis
• Kappa 72.8mg/L
• Lambda 14.6mg/L
• Kappa/Lambda Ratio 4.99

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Case 2 IgA Myeloma/MGUS

• IFE demonstrated IgA kappa band
• Hidden in Beta Region on SPE
• Since initial sample patient has had mild
  deterioration in renal function
• No significant change in patients condition
• Patient under evaluation to determine IgA
  Myeloma/MGUS

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• In both these cases, serum FLC analysis
  instigated immunofixation confirming the presence
  of a monoclonal protein that may have been
  missed.

Courtesy of S. Basu and T. Lovatt
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Case 3

• 1999
• Patient presented with headache and shoulder pain
• No osteolytic lesions
• BM biopsy low grade plasmacytosis lt10 clonal
  kappa staining
• Elevated IgA - 8.2g/L
• Diagnosis IgA kappa MGUS

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Case 3

• Follow up over 3 years
• IgA concentration remained stable
• BM biopsy plasma cells lt10
• June 2003
• IgA increased to 17.6g/L
• April 2004
• IgA substantially decreased

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Case 3 Light Chain Escape
Kühnemund Onkologie 2005 28 (suppl 3) 165
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Light Chain Escape

• Associated with
• Disease progression
• Increased tumour growth rate
• Worse prognosis
• LC escape detection may increase with
• Longer patient survival
• Modern therapies
• Monitoring Intact Ig MM patients with sFLC allows
  early detection of light chain escape
• May occur in over 10 Intact Ig MM patients

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Case 4

• 72 yr old female
• Previously treated for hypertension
• Spring 2006
• Investigated for malignancy NAD
• Diagnosed with Polymyalgia Rheumatica
• Rx Cortisone with good effect
• Autumn 2006
• Complained of Chest Pain

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Case 4

• January 2007
• Urinalysis ?presence of light chains
• Scintigraphy of skeleton showed increased uptake
  in some vertebrae together with osteoporosis
• Complaining of pain everywhere and having
  difficulty moving
• Lab Results
• Hb 10g/dL
• ESR 50 ml/hr
• Ca 2.66mmol/L
• SPE no M-component
• Serum Kappa free light chains 16.3g/L
• BM Biopsy showed 90 plasma cells

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Case 4

• Elevated kappa light chain confirmed at 2
  different sites and also Binding Site UK

IFE showed two faint bands indicating monoclonal
kappa LC production
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Case 4

• February 2007
• Patient commenced on Melphalan for 4 days
• March 2007
• 2nd cycle Melphalan
• SPE normal
• Serum kappa light chain concentrations appeared
  normal
• UPE showed evidence of Bence Jones Proteinuria
  ?kappa flc

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Case 4

• Further Investigations carried out at Binding
  Site Ltd.
• Serum sample   Kappa 3000 mg/L
•                         Lambda lt0.88 mg/L
• IFE showed similar pattern to previous samples

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Case 4
Anti-Kappa
Anti-IgG
kDa

• Sample analysed by SDS Page and Western Blotting
• Molecular weight markers defined sizes of
  proteins
• Sample contained monomer, dimer and other
  polymeric forms

116
97
58.1
29
14.3
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Case 4 Polymerisation of FLCs

• FLC molecules are usually monomers but highly
  polymeric forms do exist in a proportion of
  myeloma patients
• FreeliteTM overestimates serum free light chain
  concentrations in polymerised samples
• Can occur in patients who have undetectable serum
  FLCs by SPE and IFE
• Although the serum free light chain assay
  over-reads it is still of clinical value for
  clinicians as it can be used to monitor patients