10. Hematopoietic tumours

Question 1

Definition of multiple myeloma

Answer 1

Haematological malignancy due to plasma cells accumulating in the bone marrow, usually seen in older adults

Question 2

Morphology of multiple myeloma

Answer 2

1. Histologically:
   - Atypical plasma/plasmacytoid cells with round & eccentric nuclei
   - Chromatin arranged in clumps at the periphery, producing a clock face appearance

Question 3

Clinical features of multiple myeloma

Answer 3

1. Xray findings:
   - Punched-out areas of bone destruction without surrounding sclerosis
2. Presentation:
   - Bone pain (usually of the back)
   - Anemia
   - Renal failure
   - Prone to infection
   - Blood hyperviscosity
   - Amyloidosis
   - Neuropathies (secondary to amyloid infiltration)
3. Investigations:
   - Urine: abnormal proteins (monoclonal secretion of immunoglobulins or Bence Jones proteins, usually IgG – 55% or IgA – 25%)
   - Marrow biopsy & aspirate (abnormal & monoclonal plasma cells)
   - Flow cytometry & serum/urine electrophoresis