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Leukemia & Lymphoma

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Leukemia, Hairy Cell

It is possible that the main title of the report Leukemia, Hairy Cell is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.


  • Leukemic Reticuloendotheliosis
  • HCL

Disorder Subdivisions

  • None

General Discussion

Hairy cell leukemia (HCL) is a rare type of blood cancer characterized by abnormal changes in white blood cells known as B lymphocytes. The bone marrow creates too many of these defective cells, known as "hairy cells" because of the thin hair-like projections found on their surface. Overproduction and accumulation of hairy cells causes a deficiency of normal blood cells (pancytopenia), including an abnormal decrease of certain white blood cells (neutrophils [neutropenia]) and certain red blood cells (platelets [thrombocytopenia]). Affected individuals usually exhibit fatigue, weakness, fever, weight loss, and/or abdominal discomfort due to an abnormally enlarged spleen (splenomegaly). In addition, affected individuals may have a slightly enlarged liver (hepatomegaly) and may be unusually susceptible to bruising and/or severe infection. The exact cause of hairy cell leukemia is not known.


Leukemia & Lymphoma Society
1311 Mamaroneck Avenue
Suite 310
White Plains, NY 10605
Tel: (914)949-5213
Fax: (914)949-6691
Tel: (800)955-4572

American Cancer Society, Inc.
250 Williams NW St
Ste 6000
Atlanta, GA 30303
Tel: (404)320-3333
Tel: (800)227-2345
TDD: (866)228-4327

National Cancer Institute
6116 Executive Blvd Suite 300
Bethesda, MD 20892-8322
Tel: (301)435-3848
Tel: (800)422-6237
TDD: (800)332-8615

OncoLink: The University of Pennsylvania Cancer Center Resource
3400 Spruce Street
2 Donner
Philadelphia, PA 19104-4283
Tel: (215)349-8895
Fax: (215)349-5445

Children's Leukemia Research Association
585 Stewart Avenue, Suite 18
Garden City, NY 11530
Tel: (516)222-1944
Fax: (516)222-0457

Hairy Cell Leukemia Research Foundation
790 Estate Drive
Deerfield, IL 60015
Tel: (866)376-0046

Rare Cancer Alliance
1649 North Pacana Way
Green Valley, AZ 85614

Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
Tel: (301)251-4925
Fax: (301)251-4911
Tel: (888)205-2311
TDD: (888)205-3223

Friends of Cancer Research
1800 M Street NW
Suite 1050 South
Washington, DC 22202
Tel: (202)944-6700

Cancer Support Community
1050 17th St NW Suite 500
Washington, DC 20036
Tel: (202)659-9709
Fax: (202)974-7999
Tel: (888)793-9355

Lance Armstrong Foundation
2201 E. Sixth Street
Austin, TX 78702
Tel: (512)236-8820
Fax: (512)236-8482
Tel: (877)236-8820

For a Complete Report:

This is an abstract of a report from the National Organization for Rare Disorders (NORD). A copy of the complete report can be downloaded free from the NORD website for registered users. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational therapies (if available), and references from medical literature. For a full-text version of this topic, go to and click on Rare Disease Database under "Rare Disease Information".

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site or email

Last Updated: 2/12/2008
Copyright 1986, 1988, 1990, 1991, 1992, 1993, 1998, 2001, 2008 National Organization for Rare Disorders, Inc.

WebMD Medical Reference from the National Organization for Rare Disorders

Last Updated: May 28, 2015
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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