Highlights & Basics
- Hairy cell leukemia (HCL) is an uncommon, indolent, mature B-cell neoplasm. It is characterized by symptoms of fatigue, a markedly enlarged spleen, pancytopenia, and a distinctive histologic appearance on peripheral blood smear and bone marrow biopsy.
- HCL is not curable. However, it is highly responsive to therapy; median relapse-free survival of a decade or more has been reported.
- In asymptomatic patients with well-preserved blood counts, immediate treatment is not required.
- In symptomatic patients or those with worsening blood counts, treatment with purine analogs is recommended.
- Supportive care with antibiotics, anti-infective prophylaxis, granulocyte colony-stimulating factor, and irradiated blood products may be required as part of treatment.
Quick Reference
History & Exam
Key Factors
Other Factors
Diagnostics Tests
Treatment Options
Definition
Epidemiology
Etiology
Pathophysiology
Images
Cytospin prepared from bone marrow aspirate illustrates the typical cell cytology, with oval- to bean-shaped nuclei and moderate amounts of cytoplasm with irregular cytoplasmic borders (Wright Giemsa 100×oil)
Sections of core biopsy demonstrate lymphocytes with obvious cytoplasm within the marrow interstitium, associated with dilation of marrow sinuses and red blood cell collections (H&E 50×oil)
Citations
Parry-Jones N, Joshi A, Forconi F, et al. Guideline for diagnosis and management of hairy cell leukaemia (HCL) and hairy cell variant (HCL-V). Br J Haematol. 2020 Dec;191(5):730-7.[Abstract][Full Text]
Troussard X, Maître E, Paillassa J. Hairy cell leukemia 2024: update on diagnosis, risk-stratification, and treatment - annual updates in hematological malignancies. Am J Hematol. 2024 Apr;99(4):679-96.[Abstract][Full Text]
Grever MR, Abdel-Wahab O, Andritsos LA, et al. Consensus guidelines for the diagnosis and management of patients with classic hairy cell leukemia. Blood. 2017 Feb 2;129(5):553-60.[Abstract][Full Text]
National Comprehensive Cancer Network. NCCN clinical practice guidelines in oncology: hairy cell leukemia [internet publication].[Full Text]
Robak T, Matutes E, Catovsky D, et al. Hairy cell leukaemia: ESMO clinical practice guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2015 Sep;26(suppl 5):v100-7.[Abstract][Full Text]
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