NOTE

🌱 created from: chronic myelogenous leukemia

biology_of_chronic_myelogenous_leukemia

• Philadelphia chromosome
• Three types of fusion proteins based on location of breakpoint in BCR gene:
  • p210:
    • Classic breakpoint (>95% of pts); (also seen in 30% Ph+ ALL)
  • p230:
    • Alternative breakpoint; found in only rare cases (<1%)
  • p190:
    • Also rare (<1%); (common breakpoint in Ph+ ALL, 70%)
• A minority of pts (<5%) may harbor a variant translocation (eg, t(9;14;22))
  • → testing at dx by both cytogenetics (karyotype, FISH) & molecular (PCR) important;
  • need to confirm fusion type (eg, p210) & splice type (e13 vs. e14a2) → impact on response