Etiology

 • t(9;22) → BCR-ABL fusion (Philadelphia chromosome)

Pathogenesis

 • Tyrosine kinase activation → ↑ mature granulocytes

Clinical features

 • Fatigue, weight loss, night sweats
 • Massive splenomegaly → early satiety
 • May progress to blast crisis (AML/ALL)

Lab findings

 • Marked leukocytosis (>100,000/µL)
 • ↑ Basophils, eosinophils
 • ↓ Leukocyte alkaline phosphatase (LAP)
 • BCR-ABL positive

Treatment

 • Imatinib (TKI)
 • Stem cell transplant if resistant