Myeloma Flashcards
What is myeloma?
Cancer of the plasma cells- antibody producing B-lymphocytes
It produces a large quantity of a specific paraprotein (abnormal antibody)
What is multiple myeloma?
When myeloma affects multiple areas of the body
What is MGUS?
Monoclonal gammopathy of undetermined significance-
Premalignant state- incidental finding of paraprotein with no symptoms (progression rate only 1% per year)
What is smouldering myeloma?
In between MGUS and myeloma- malignant myeloma but with no associated organ damage (10% progression rate)
What are the risk factors for myeloma?
Age- 65 median
Male
Black
Obesity
Family history
Pathophysiology of myeloma?
In normal circumstances- plasma cells produce certain antibodies (immunoglobulins)
In myeloma- cancer in one of these -> rapid uncontrolled proliferation
This leads to a monoclonal paraprotein- significant abundance of one type of Ig, usually IgG (or part of, ie only light chains)
What is usually found in the urine of a myeloma patient?
Bence Jones protein- free light chains
What are the 4 hallmark myeloma features?
CRAB
C- calcium elevation
R- renal failure
A- anaemia
B- bone lesions (and pain)
What causes renal failure in myeloma patients?
Paraprotein deposition in renal tubules -> glomerulonephritis
Also affected by hypercalcaemia, dehydration, amyloidosis, and meds used to treat the condition
What causes anaemia in myeloma patients?
Cancerous cells infiltrate bone marrow , leading to pancytopenia via suppression of other lines
Most common complication of myeloma!
What causes bone lesions in myeloma?
Dysregulation between osteoclast and osteoblast activity, affecting bone structure
Commonly affects spine, skull, long bones and ribs
What causes hypercalcaemia in myeloma patients?
Increased osteoclast activity -> high levels of calcium from destroyed bones -> increased calcium resorption
What are plasmacytomas?
Cancerous plasma cell tumours found in bone or soft tissue
How does myeloma present?
Persistent bone pain
Pathological fractures (due to weakened spots caused by myeloma bone disease)
CRAB symptoms
Red flag symptoms- unexplained fatigue, weight loss, and fever
How is myeloma investigated?
First investigations-
FBC -> pancytopenia
Raised calcium, ESR, and plasma viscosity
U&E for renal signs
Rouleaux on smear
more specific tests-
Serum protein electrophoresis to identify paraprotein
Urine electrophoresis to show Bence Jones protein
Imaging for bone lesions- MRI first line XR second
diagnostic tests
Bone marrow aspirate and trephine biopsy, with plasma cell phenotyping
