Leukemia, Hairy Cell

Leukemia, Hairy Cell

National Organization for Rare Disorders, Inc.


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.


Onset of hairy cell leukemia is usually gradual. Symptoms are nonspecific and may include a general feeling of ill health (malaise), fatigue, weakness, fever, night sweats, and/or weight loss. In addition, affected individuals may experience abdominal pain and a feeling of abdominal fullness due to an abnormally enlarged spleen (splenomegaly).

In some cases, affected individuals may have a slightly enlarged liver (hepatomegaly) and may be unusually susceptible to bruising and/or severe, frequent infections. These infections were often the most serious complication of hairy cell leukemia, but occur rarely with advances in treatment.


The exact cause of hairy cell leukemia is unknown.

The specific symptoms of hairy cell leukemia are due to overproduction of abnormal "hairy" cells, which results in a deficiency of the three main types of blood cells - red and white blood cells and platelets. Red blood cells deliver oxygen to the body, white blood cells help fight infections, and platelets assist in clotting to stop blood loss.

Affected Populations

Hairy cell leukemia is a rare disorder that affects males four times more often than females (M4:F1). Hairy cell leukemia affects about 6,000 persons in the United States. Approximately 600-800 new cases are diagnosed each year. Most of the affected individuals are males 50 years of age or older. However, the disorder may occur in individuals between 20 to 80 years of age.

Hairy cell leukemia accounts for one to two percent of all cases of adult leukemia. It was first identified in 1958.

Standard Therapies

Until recently, treatment of hairy cell leukemia consisted of surgically removing the spleen (splenectomy). In rare cases, in which individuals do not respond to drug treatments, a splenectomy may still be performed. Chemotherapy drugs, specifically purine analogs such as cladribine and pentostatin, are now the initial treatment option for most individuals with hairy cell leukemia.

The drug cladribine (Leustatin©) has been approved by the Food and Drug Administration (FDA) for treatment of HCL. This drug interferes with the development of cancer cells and has proven to be an effective drug in the treatment of hairy cell leukemia. For more information, contact:

Ortho Biotech Products

430 Route 22 E.

Bridgewater, NJ 08807-0914

Phone: 908-541-4000

The orphan drug pentostatin (Nipent) has been approved by the FDA for affected individuals who do not respond to initial therapy for hairy cell leukemia. According to studies, the drug produced "durable complete responses" in individuals with hairy cell leukemia. The drug is manufactured by SuperGen, Inc. For more information, contact:

SuperGen, Inc.

Two Annabel Lane, Suite 220

San Ramon, CA 94583

Tel: (925) 327-0200

Fax: (925) 327-7347

Approximately 10 percent of individuals will not respond to treatment with chemotherapy drugs. In addition, some individuals cannot take such drugs. In such cases, individuals may be treated with biological therapies such as alpha interferon. Biologic therapies attempt to use the body's immune system directly or indirectly to treat the malignancy.

The orphan drug alpha interferon has been approved by the FDA for use in the treatment of hairy cell leukemia. The drug is manufactured by Hoffman-LaRoche and Schering Plough. Interferon is a hormone naturally produced by the body to fight viral infections. Treatment with alpha interferon may include daily injections for up to six months, followed by maintenance injections three times weekly. Side effects mimic flu-like symptoms, which diminish over time.

Investigational Therapies

A biological therapy known as rituximab (Rituxan©) has been used to treat individuals with hairy cell leukemia who do not respond to conventional therapy. Rituximab is an antibody that attaches itself to hairy cells. The drug has been approved for non-Hodgkin's lymphoma and is being studied to determine its long-term safety and effectiveness as a therapy for hairy cell leukemia.

Interleukin-2 has been used on an experimental basis to restore natural killer cell activity in hairy cell leukemia.

The drug deoxycoformycin is being used in clinical trials on patients with hairy cell leukemia. Information about obtaining this drug can be located through the Comprehensive Cancer Center (Dr. Eric Kraut), Ohio State University, Columbus, Ohio, or the Investigational Drug Branch of the National Cancer Institute in Bethesda, Maryland.

Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.

For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:

Tollfree: (800) 411-1222

TTY: (866) 411-1010

Email: prpl@cc.nih.gov

For information about clinical trials sponsored by private sources, contact:




Bennett JC, Plum F, eds. Cecil Textbook of Medicine. 20th ed. Philadelphia, PA: W.B. Saunders Co; 1996:929-31.

Hoffman R, et al, eds. Hematology Basic Principles and Practice, 2nd ed. New York, NY: Churchill-Livingstone, Inc; 1995:1323-29.


Riccioni R, Galimberti S, Petrini ML, Hairy cell leukemia. Curr Treat Options Oncol. 2007;[Epub ahead of print].

Swords R, Giles F. Hairy cell leukemia. Med Oncol. 2007;24:7-15.

Hoffman MA. Clinical presentations and complications of hairy cell leukemia. Hematol Oncol Clin North Am. 2006;20:1065-1073.

Flinn IW, Kopecky KJ, Foucar MK, et al. Long-term follow-up remission duration, mortality, and second malignancies in hairy cell leukemia patients treated with pentostatin. Blood. 2000;96:2981-86.

Wu ML, Kwaan HC, Goolsby GL. Atypical hairy cell leukemia. Arch Pathol Lab Med. 2000;124:1710-13.

Zinzani P, Magagnoli M, Bendandi M, et al. Long-term follow-up of hairy cell leukemia patients treated with 2-chlorodeoxyadenosine. Haematologica. 2000;85:922-25.

Johnston JB, Eisenhauer E, Wainman N, Corbett WE, Zaentz SD, Daeninck PJ. Long-term outcome following treatment of hairy cell leukemia with pentostatin (Nipent): a National Cancer Institute of Canada study. Semin Oncol. 2000;27:32-36.

Tetreault SA, Robbins BA, Saven A. Treatment of hairy cell leukemia-variant with cladribine. Leuk Lymphoma. 1999;35:347-54.

Piro LD, Carrera CJ, Carson DA, Beutler E. Lasting remissions in hairy-cell leukemia induced by a single infusion of 2- chlorodeoxyadenosine. N Engl J Med. 1990;322:1117-21.

van Norman AS, Nagorney DM, Martin JK, Phyliky RL, Ilstrup DM. Splenectomy for hairy cell leukemia; a clinical review of 64 patients. Cancer. 1986;57:644-48.

Thompson JA, Brady J, Kidd P, Fefer A. Recombinant alpha-2 interferon in the treatment of hairy cell leukemia. Cancer Treatment Rep. 1985;7-8:791-93.

Groopman JE. Therapeutic options in hairy cell leukemia. Semin Oncol. 1985;12:30-34.


Besa EC. Hairy Cell Leukemia. Emedicine Journal, July 11 2006. Available at: http://www.emedicine.com/med/topic937.htm Accessed on: February 3, 2007.

Hairy Cell Leukemia. Mayo Foundation for Medical Education and Research. February 2, 2006. Available at: http://www.mayoclinic.com/health/hairy-cell-leukemia/DS00673/DSECTION=4 Accessed on: February 3, 2007.


Leukemia & Lymphoma Society

1311 Mamaroneck Avenue

Suite 310

White Plains, NY 10605

Tel: (914)949-5213

Fax: (914)949-6691

Tel: (800)955-4572

Email: infocenter@LLS.org

Internet: http://www.LLS.org

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

Internet: http://www.cancer.org

National Cancer Institute

6116 Executive Blvd Suite 300

Bethesda, MD 20892-8322


Tel: (301)435-3848

Tel: (800)422-6237

TDD: (800)332-8615

Email: cancergovstaff@mail.nih.gov

Internet: http://www.cancer.gov

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

Email: hampshire@uphs.upenn.edu

Internet: http://www.oncolink.upenn.edu

Children's Leukemia Research Association

585 Stewart Avenue, Suite 18

Garden City, NY 11530

Tel: (516)222-1944

Fax: (516)222-0457

Email: info@childrensleukemia.org

Internet: http://www.childrensleukemia.org

Hairy Cell Leukemia Research Foundation

790 Estate Drive

Deerfield, IL 60015


Tel: (866)376-0046

Email: genefar@comcast.net

Internet: http://www.hairycellleukemia.org

Rare Cancer Alliance

1649 North Pacana Way

Green Valley, AZ 85614


Internet: http://www.rare-cancer.org

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

Internet: http://rarediseases.info.nih.gov/GARD/

Friends of Cancer Research

1800 M Street NW

Suite 1050 South

Washington, DC 22202

Tel: (202)944-6700

Email: info@focr.org

Internet: http://www.focr.org

Cancer Support Community

1050 17th St NW Suite 500

Washington, DC 20036

Tel: (202)659-9709

Fax: (202)974-7999

Tel: (888)793-9355

Internet: http://www.cancersupportcommunity.org/

Lance Armstrong Foundation

2201 E. Sixth Street

Austin, TX 78702

Tel: (512)236-8820

Fax: (512)236-8482

Tel: (877)236-8820

Email: media@livestrong.org

Internet: http://www.livestrong.org

For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders, Inc.® (NORD). Cigna members can access the complete report by logging into myCigna.com. For non-Cigna members, a copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see http://www.rarediseases.org/search/rdblist.html.

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use . How this information was developed to help you make better health decisions.

Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.