Concepts in malignant haematology

Question 1

What is malignant haemopoeisis?

Answer 1

increased number of dysfunctional cells with loss of haemopoietic reserve
1+ of:
-increased proliferation
-lack of differentiation
-lack of maturation
-lack of apoptosis

Question 2

Describe how genetic/epigenetic and environmental factors interact to cause malignant haemopoeisis?

Answer 2

Somatic mutation in regulatory genes:

• driver mutations (cause cancer growth, may need many)
• passenger mutations (increase cell’s capacity to acquire a driver)

Multiple hit vs single event

recurrent cytological abnormalities not causal in most but contributory

Question 3

How does a cancer become chemotherapy resistant?

Answer 3

cancer cells corrects itself to become resistant to chemo = chemo resistant recurrence

Question 4

Describe the concept of ‘clonal’ when discussing haematological malignancy?

Answer 4

In malignancy there is monoclonal expansion - all the cells come from 1 single parent cell that has a genetic marker which is shared. (however there can be heterogeneity within this as daughter cells acquire diff. properties)

Normal haempoeisis is polyclonal - the cells come from many different parent cell