myeloma Flashcards
what is the pathophysiology of myeloma?
- cancer of the plasma cells
- plasma B cells become activated to produce one type of antibody
- 50% of the time this will be IGg type
- these antibodies are called monoclonal paraprotein
what happens to the blood profile of someone with myeloma?
cancerous plasma cells invade the bone marrow. This is described as bone marrow infiltration.
This causes suppression of the development of other blood cell lines leading to
anaemia (low red cells),
neutropenia (low neutrophils)
and thrombocytopenia (low platelets).
how does myeloma affect the body?
- myeloma bone disease
- myeloma renal disease
- plasma viscosity
what are the e features of myeloma?
C – Calcium (elevated)
R – Renal failure
A – Anaemia (normocytic, normochromic) from replacement of bone marrow.
B – Bone lesions/pain
who should you suspect myeloma in?
anyone over 60 with persistent bone pain, particularly back pain, or an unexplained fractures
how will general bloods appear in myeloma?
FBC (low white blood cell count in myeloma)
Calcium (raised in myeloma)
ESR (raised in myeloma)
Plasma viscosity (raised in myeloma)
which investigations would you do when suspecting myeloma?
B – Bence–Jones protein (request urine electrophoresis)
L – Serum‑free Light‑chain assay
I – Serum Immunoglobulins
P – Serum Protein electrophoresis
Bone marrow biopsy is necessary to confirm the diagnosis of myeloma and get more information on the disease.
which imaging should you do when you diagnose myeloma?
Whole body MRI
Whole body CT
Skeletal survey (xray images of the full skeleton)
what is the pathophysiology of myeloma bone disease?
- cytokines released from plasma cells increase osteoclast activity and reduce osteoblast activity, resulting in an increase in bone resorption
- bone metabolism is patchy, especially in skull, spine, long bones and ribs, can lead to pathological fractures
- osteolytic lesions can form
what are plasmacytomas?
People with myeloma can also develop plasmacytomas.
These are individual tumours made up of the cancerous plasma cells.
They can occur in the bones, replacing normal bone tissue or can occur outside bones in the soft tissue of the body.
what is the pathophysiology of myeloma renal disease?
High levels of immunoglobulins (antibodies) can block the flow through the tubules
Hypercalcaemia impairs renal function
Dehydration
Medications used to treat the conditions such as bisphosphonates can be harmful to the kidneys
what are complications caused by increased plasma viscosity?
Easy bruising
Easy bleeding
Reduced or loss of sight due to vascular disease in the eye
Purple discolouration to the extremities (purplish palmar erythema)
Heart failure
what are risk factors for myeloma?
Older age Male Black African ethnicity Family history Obesity
what are some xray signs you may see in myeloma?
Punched out lesions
Lytic lesions
“Raindrop skull”
which chemotherapy management requires thromboprophylaxis?
venous thromboembolism prophylaxis with aspirin or low molecular weight heparin whilst on certain chemotherapy regimes (e.g. thialidomide)
as there is a higher risk of developing a thrombus.
what is the first line management for myeloma?
chemotherapy with:
Bortezomid
Thalidomide
Dexamethasone
how can myeloma bone disease be managed?
Myeloma bone disease can be improved using bisphosphonates. These suppress osteoclast activity.
Radiotherapy to bone lesions can improve bone pain.
Orthopaedic surgery can stabilise bones (e.g. by inserting a prophylactic intramedullary rod) or treat fractures.
Cement augmentation involves injecting cement into vertebral fractures or lesions and can improve spine stability and pain
