Multiple myeloma

Question 1

What is MM?

Answer 1

haematological malignancy characterised by proliferation of terminally differentiated plasma cells.

They infiltrate bone marrow.

Question 2

What are symptoms of MM?

Answer 2

plasma cells infiltrate bone marrow causing bone pain, symptoms of hypercalcaemia, and fragility frcatures.

infiltration also causes anaemia and can cause bleeding

plasma cells secrete paraprotein which can result in light chain deposition in renal tubules, causing kidney damage e.g. haematuria, proteinuria, BJ protein

Question 3

What is MGUS/

Answer 3

Risk factor for MM, no symptoms

Question 4

What Ix?

Answer 4

Serum and urine electrophoresis: paraprotein in blood, BJ in urine. Can also do serum free light chains

bloods: FBC, U+Es (renal impairment), Ca (raised)

Whole body CT/x-rays: looking for lytic lesions e.g. pepperpot skull, general osteopenia. MRI is more sensitive.

Bone marrow aspiration and biopsy: diagnostic which helps differentiate from MGUS. Shows monoclonal plasma cell infiltration > 10%.

Question 5

What is diagnostic criteria for MM?

Answer 5

Must have >10% neoplastic plasma cells in BM + either

• CRAB (evidence of end organ damage)
• Biomarker of malignancy e.g. plasma cells in BM >60%, SFLC ratio >100, >1 focal lesion on MRI.

Question 6

What are differentials for MM?

Answer 6

MGUS
Solitary plasmocytoma 
Smouldering myeloma
Amlyoidosis
NHL

Question 7

What is Rx for MM/

Answer 7

Autologous BMT in younger patients

Chemo including steroid and thalidomide for all

Supportive for all: bisphosphonates, prednisolone, blood transfusion

Radio for bone pain or SCC

Question 8

What are complications of MM

Answer 8

Spinal cord compression
AKI/ renal failure
Fragility fractures
infections