Blood/Blood Cells and Cellular Components ›› Lymphocytes ›› Abnormal

Hairy Cell Leukemia*


Click Here for Full Size

---

› Microscopic Features:

• Peripheral blood smear shows lymphocytes with hair-like cytoplasmic projections
• Abnormal lymphocytes with hair-like projections are intermediate in size
• Lacks a nucleolus
• The neoplastic cells typically involve the Red Pulp area of the Spleen (as opposed to splenic Marginal zone lymphoma which involves the White pulp)

› Normal % blood-PB, marrow-BM, lymphoid tissue-LN:

• PB: None
• BM: None
• LN: None

› May Resemble:

• Splenic Marginal Zone Lymphoma [Compare]
• Reactive lymphocyte [Compare]
• CLL [Compare]

› Differential Diagnoses:

Splenic Marginal Zone Lymphoma Reactive Lymphocytosis CLL

› Classic Immunophenotype:

• CD19+
• CD20+
• CD5-
• CD10-
• CD103+
• CD11c+
• CD25+
• Annexin1+

› Cartoon Image:


Click and drag

for direct comparison
› Misc:

• Many cases present with splenomegaly, cytopenia or pancytopenia (many with monocytopenia), and a dry bone marrow aspirate.