Myeloma

Question 1

Myeloma pathophysiology

Answer 1

Bone marrow malignancy causing a clonal population of abnormal plasma cells

They secrete abnormal antibodies - IgG,E,D,M kappa and lambda - paraproteins

Question 2

Presentation of myeloma

Answer 2

CRAB (end organ damage)

Hypercalcaemia - bone lytic lesions, polyuria, polydipsia, constipation

Renal disease - AKI due to accumulation of complexes

Anaemia - aplastic anaemia - fatigue, SOB

Bone pain - pathological fractures and osteolytic bone lesions

Other:

• recurrent infections - neutropenia
• abnormal bleeding - thrombocytopenia
• hyperviscosity - headaches, visual disturbances
• neuropathy - spinal cord compression

Question 3

Complications of myeloma

Answer 3

Aplastic anaemia - pancytopaenia

Thrombocytopenia - abnormal bleeding

Bone pain

Renal disease - complexes deposit in the glomerulus

Plasmacytomas

Impaired immune system

Amyloidosis - abnormal antibodies deposited in organs such as the heart

Question 4

Presentation of hypercalcaemia

Answer 4

Polyuria
Polydipsia
Abdo pain
Constipation
Lethargy 
Confusion

Question 5

Defining factors of myeloma

Answer 5

SLIM

Sixty percent (60%) bone marrow plasmacytosis

Light chain ratio > 100

MRI - > 1 focal lesion of > 5mm

Must be accompanied by >10% clonal population of bone marrow plasma cells

Question 6

Myeloma investigations

Answer 6

Bloods - FBC, U+Es, LFTs, Bone profile (Ca2+, phosphate, ALP), vitamin D

Immunoglobulin screen - IgG, M, A - maybe polyclonal or monoclonal

Urine sample - Bence - Jones proteins

Bone marrow biopsy and aspiration - Flow cytometry

Paraprotein detected by electrophoresis

Paraprotein ratio: serum-free light chains (SFLC) - monoclonal protein (M - protein)

CT CAP

MRI - whole body

Question 7

Important examination for myeloma

Answer 7

Neurological exam - exclude spinal cord compression

Question 8

Serum-free light chains (SFLC)

Answer 8

Levels of kappa and lambda light chains detected in serum

Gives ratio (if just high kappa - high likelihood of monoclonal population)

Question 9

Asymptomatic myeloma - smouldering

Answer 9

Paraprotein > 30g/l

Clonal bone marrow plasma cells - 10 - 60%

Absence of any myeloma defining events or amyloidosis

Question 10

Treatment of myeloma

Answer 10

Intensive - chemotherapy (VTD) + autologous stem cell transplant

Non intensive - chemotherapy

Less than 30% stay in remission

Question 11

How does myeloma cause anaemia

Answer 11

1. Shift from myeloid progenitor to lymphoid progenitor cells
2. More plasma cells taking up bone marrow space so less RBC production
3. Renal impairment so less erythropoietin

Question 12

Staining for myeloma

Answer 12

Congo red

Question 13

VTD

Answer 13

Chemotherapy
Thalidomide
Dexamethasone