Myeloma Flashcards
Pathophysiology
- Clonal expansion of abnormal, proliferating plasma cells producing a monoclonal paraprotein (IgG or IgA)
What would be seen in the urine in people with Myeloma
Excretion of light chains in the urine due to paraproteinaemia
What age group does Myeloma tend to effect
Elderly
Three clinical features of a myeloma
- Bone destruction
- Bone marrow infiltration with plasma cells
- Kidney Injury
Consequence of bone destruction
Fractures of long bones or vertebral collapse
Hypercalcaemia
Plasmacytosis
Consequence of Bone marrow infiltration with plasma cells
Anaemia
Thrombocytopenia
How does kidney injury occur
Position of light chains in renal tubules
Hypercalcaemia
Cytogenetic analysis should show what in patients with myeloma
FISH should show abnormal chromosome 13 and hypodiploidy
How else does myeloma effect the bone
- Dysfunction of bone remodelling
- Leads to lesions in spine, skull + long bones
Increased osteoclastic activity with no increased osteoblast formation of bone
Symptoms of Myeloma
- Bone pain (backache)
- Anaemia
- Recurrent infections
- Renal failure
- Hypercalcaemia
- Thrombocytopenia
What should we see in blood tests in people with myeloma
NORMAL BLOOD COUNT
What is the erythrocyte sedimentation rate in myeloma
High
What should we see on a blood film
Rouleaux formation as a consequence of paraprotein formation and plasma cells
Serum calcium levels in myeloma
Raised
Total protein count in myelomas
Raised
What would radiological signs of myeloma be
- Skeletal survey - Show characteristics of lytic lesions, most easily seen in the skull
- MRI spine is useful is there is back pain (shows collapse)
How is Symptomatic Myeloma diagnosed
If either the following is present:
- Significant Paraproteinaemia
- Increased bone marrow plasma cells
How is asymptomatic myeloma diagnosed
- Significant paraproteinaemia + marrow plasmocytosis
What is considered significant paraproteinaemia
IgG>30g/dL
What is a plasmacytoma
- Isolated tumour of neoplastic plasma cells
What indicates a poor prognosis of myeloma
- Reduced serum albumin
- Increased serum betamicorglobulin
- Increased LDH
Is Myeloma curable
No
What ethnicity does Myeloma tend to effect
Afro-caribbeans
How does Myeloma cause back pains
Activation of osteoclasts increase bone turnover and lytic lesions
Osteoblasts are inhibited reducing new bone formation
What two compounds activate osteoclasts
RANK ligans and IL-3
What molecules inhibit osteoblasts
HGF and Dkk-1
Why does myeloma result in recurrent bacterial infections
Neutropenia - causes high neutrophil count in healthy individuals
How is Myeloma treated
All patients given bisphosphonate
Name a bisphosphonate
Zolendronbte
Role of Bisphosphonate
Reduces bone pain and fracture rates
Why do we avoid NSAIDS
Risk of renal impairment
How is anaemia corrected
Transfusion of RBCs and erythropoietin
how to prevent renal damage
And rehydrate with 3L a day to prevent further renal damage
How is acute renal failure from myeloma treated
Renal dialysis
Describe the chemotherapy used for myeloma
- CTD - Cyclophosphamide, Thalidomide, Dexamethasone
2. VAD (Vincristine, Adriamycin, Dexamethasone)
How many cycles of CTD can you do
8
How many cycles of VAD can you do
6
When is CTD chosen as treatment
Less fit people
How do Bisphosphonates function
They inhibit osteoclasts so reduce bone resorption
