Multiple Myeloma

Question 1

What is multiple myeloma?

Answer 1

Multiple myeloma is a malignant plasma cell dyscrasia characterized by the proliferation of abnormal plasma cells in the bone marrow. These plasma cells secrete monoclonal antibodies (most commonly of the Ig subtype) and antibody fragments into the serum and the urine

Question 2

What is the acronym for multiple myeloma?

Answer 2

CRAB HAI:
HyperCalcaemia – arises primarily owing to increased osteoclast-mediated bone resorption. Results in: moans (painful bones), stones (renal stones), groans (GI symptoms) and psychiatric moans (neurological effects such aslethargy, fatigue, memory loss, psychosis, depression)
Renal impairment – occurs because of multiple factors (eg. light chain deposition in the kidneys and hypercalcaemia)
Anaemia – other cytopenias (eg. thrombocytopenia and leukopenia) can also occur due to marrow infiltration by the tumour
Bone pathology – Back pain is very common. Osteolytic lesions are common, which can lead to pathological fractures and vertebral compression fractures
Hyperviscosity – can present with headache, visual disturbance and thrombosis
Amyloidosis (AL subtype) – can have multiple sequelae including cardiac failure and neuropathy
Infection

Question 3

What is the initial diagnostic investigation for multiple myeloma?

Answer 3

Bone marrow aspirate and biospy for over 10% of plasma cells in bone marrow

Additional investigations is serum/urine electrophoresis showing paraprotein spike of IgG

Serum free light chain assay

Question 4

What acute emergency occurs in multiple myeloma?

Answer 4

Acute renal failure – swift treatment of volume depletion is critical, as well as early involvement of renal physicians
Hypercalcaemia – fluid and bisphosphonates needed
Hyperviscosity – requires plasmapheresis
Spinal cord compression – should be treated as a radiotherapy emergency

Question 5

What is the management of multiple myeloma?

Answer 5

Haematopoietic stem cell transplant
-> requires induction therapy with non chemo therapeutics like thalidomide with mono cloacal antibody daratumumab

Question 6

What indicates prognosis in multiple myeloma?

Answer 6

Worse prognosis with:
High LDH
Very high or low B2 microglobulin
High CRP

Question 7

What is the X ray findings in yeloma patients?

Answer 7

Raindrop skull

Question 8

What investigation is used to diagnose myeloma?

Answer 8

Serum paraprotein electrophoresis: Raised concentrations of monoclonal IgA/IgG proteins in serum

Whole body MRI

GOLD STANDARD: Bone marrow aspirate:≥10% monoclonal plasma cells,≥60% clonal bone marrow plasma cells
Urine protein electrophoresis: Raised light chains