Myeloma + MGUS

Question 1

Describe the classical features of myeloma.

Answer 1

1. clonal proliferation of plasma cells (>10% BM)
2. osteolytic bone lesions… hypercalcaemia
3. renal disease/AKI: monoclonal light chains deposit in glomerular basement membrane + precipitate as casts in DCT
4. anaemia +/- neutropaenia
5. immunodeficiency

Question 2

You suspect a patient to have myeloma. What blood tests do you request and what would these show?

Answer 2

1. FBC: anaemia, neutropaenia
2. peripheral blood film: rouleaux
3. ESR/plasma viscosity: raised
4. U+E/creatinine: renal failure
5. calcium: hypercalcaemia
6. total protein: raised
7. quantitative Ig levels: raised IgG (sometimes IgA)
8. paraprotein levels: >30 (diagnostic)
9. protein electophoresis + serum free light chain assay: confirms presence + indicates type of paraprotein
10. serum immunofixation: to confirm presence of paraprotein

Question 3

You suspect a patient to have myeloma and blood results support this. What further tests would you request?

Answer 3

1. BMAT: send samples for flow cytommetry (clonal plasma cells >10%), immunohistochemistry, immunophenotyping + FISH
2. full-body MRI
3. X-ray any symptomatic areas

Question 4

What are the usual management options for myeloma?

Answer 4

1. chemotherapy e.g. CYCLOPHOSPHAMIDE + THALIDOMIDE + DEXAMETHASONE
2. +/- autologous STC
3. bisphosphonate Tx e.g. ZOLENDRONIC ACID 4mg IV monthly (for bone protection + improved survival)

In some selected patients: BM transplant (can be curative)

Question 5

What is the difference between myeloma and MGUS?

Answer 5

No fundamental difference as these is a clonal population of plasma cells in the BM which share an abnormal phenotype but in MGUS there is <10% plasma cells in BM, <30g/L serum paraprotein and no attributable end-organ damage.