CLL

Question 1

Why do we do direct FISH preps on CLL and not cultures?

Answer 1

The abnormality rate of CLL by g-banding is lower than for FISH

Also - lymphoid cells are not as amenable to culture as myeloid cells, their mitotic activity is very low

Question 2

Is CLL characterised mainly by genomic imbalances or by rearrangements?

Answer 2

Genomic imbalance.

Don’t typically see fusions.

Question 3

What FISH do we set up on CLL samples?

Answer 3

P53 ATM

CEP12/D13S319/13q34

Question 4

Why do we set-up this FISH?

Answer 4

To detect prognostically significant abnormalities;

• trisomy 12 - intermediate
• 13q14 deletions - mono or biallelic - historically good but biallelic dels associated with shorter overall survival
• 17p deletions (P53) - very high risk
• 11q deletions (ATM) - high risk/poor

Question 5

What symptoms might you expect in a CLL patient?

Answer 5

Slow growing condition so sometimes none - found by chance on a routine blood test - asymptomatic

If disease is more advance;

• recurrent infections
• splenomegaly
• tiredness
• weight loss
• fever