Chronic Myeloid Leukaemia

Question 1

Chronic Myeloid Leukaemia - Philadelphia Chromosome

Answer 1

Philadelphia chromosome present in >95% of patients
= Translocation between long arm of chromosome 9 and 22 t(9:22)(q34,q11) > part of ABL photo-oncogene from chromosome 9 being fused with BCR gene from chromosome 22 resulting in BCR-ABL gene = fusion protein which has tyrosine kinase activity IN EXCESS OF NORMAL

Question 2

CML - Presentation

Answer 2

• 40-50 (middle aged) w anaemia, weight loss, abdominal discomfort
• splenomegaly may be marked
• spectrum of myeloid cells in peripheral blood
• decrease leukocyte alkaline phosphatase
• may undergo blast transformation (AML in 80%, ALL in 20%)

Question 3

CML - Mx

Answer 3

1) IMATINIB = 1st line
Inhibitor = 1st line = inhibitor of tyrosine kinase assoc with BCR-ABL defect
V high response in chronic phase CML
2) Hydroxyurea
3) Interferon-alpha
4) Allogenic bone marrow transplant