Myeloma Flashcards
Who is myeloma most common in?
Elderly ~70yo
Afro-caribbean’s
What gene mutation allows cells to grow uncontrollably in Myeloma?
RAS gene
What does the malignant proliferation of plasma cells cause?
The abnormal monoclonal proliferation of plasma cells leads to excess production of a paraprotein (Bence Jones). The increased volume of them means they precipitate out leading to renal tubular damage
Increased osteolytic activity
Infiltrate bone marrow
What do the monoclonal antibodies Bence Jones proteins cause in the kidneys?
They are usually reabsorbed in the PCT but large quantities means they precipitate out as casts
They cause tubular inflammation and destruction –> AKI –> decreased erythropoeitin –> anaemia
What causes AKI in myeloma?
Amyloid deposition
Tubular damage from bence jones protein
Hypercalcarmia leading to dehydration
What does increased osteolytic activity lead to?
calcium release –> hypercalcaemia –> dehydration, thirst, nausea, constipation
pathological fractures
lytic lesions (often vertebral) –> spinal cord compression
Bone pain
What does bone marrow infiltration lead to?
Bone destruction –> bone pain
Marrow failure: normocytic, normochromic anaemia and recurrent infection
What are the classical symptoms of myeloma?
CRAB: Calcium elevation Renal complications Anaemia Bone disease
How does myeloma progress?
Monoclonal gammopathy of undetermined significance (MGUS) –> smouldering/indolent myeloma –> myeloma
What investigations are ordered if myeloma is suspected and why?
Which would you do first?
Bloods
Urine - bence jones protein presence
X-Ray - lytic lesions and pepper pot skull
FIRST: Serum Protein Electrophoresis - paraprotein presence
Bone marrow - % plasma cells and determine phenotype (flow cytometry)
What do you look for in the bloods for a patient with suspected myeloma?
Anaemia Paraproteinaemia decreased normal antibodies hypercalcaemia but normal phosphate and ALP Increased urea Increased creatinine increased plasma viscosity/ESR
How is myeloma diagnosed?
All 3:
> 10% monoclonal antibodies in marrow
Monoclonal protein in serum/urine
1 of CRAB
How is MGUS/Smoldering myeloma managed?
Monitoring
What is the difference between MGUS and smoldering myeloma(SMM)?
MGUS isn’t cancer - benign, asymptomatic condition characterised by excess monoclonal protein
SMM is a precursor to multiple myeloma - raised monoclonal protein but no CRAB criteria
What other management is used for myeloma?
Neuropathic pain control Corticosteroids + radio - bone pain Zoledronic acid - bone disease Bisphosphonates Infection prevention
