Hairy Cell Leukemia

Overview

• Rare, chronic B cell lymphoproliferative disorder
  • represents 2% of leukemias
  • avg age is 52 yrs
  • male> female with 4:1 ratio
  • caucasians 4x more likely to develop than others
• assembles cytokines like TNF, which may cause pancytopenia by suppressing BM
• At presentation, 25% with abdominal pain/splenomegaly, 25% with fatigues/weakness, 25% with bleeding, 25% asymptomatic
• Indications for treatment include cytopenias, splenomegaly, constitutional symptoms, and treatment is often not initiated immediately; 10% never need treatment. Purine analogs are used as monotherapy initially. Either cladribine or pentostatin gives the median first-time patient a ten-year remission
  
  

Pathology

• "hairy" projections are from villous cytoplasm and are seen on light and electron microscopy.
• Bone marrow may be difficult to aspirate as it may be "dry" due to fibrosis in which case repeat core biopsies should be attempted. The biopsy shows a pattern of infiltration by the malignant cells and fibrosis
  
  

(Ellen Eaton MD, 7/23/10)