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Familial Chronic Lymphocytic Leukemia Study

The National Cancer Institute (NCI) is studying families with multiple cases of chronic lymphocytic leukemia (CLL), the most common leukemia in adults in the Western Hemisphere. CLL is described as one of the "lymphoproliferative disorders".  If CLL runs in your family, NCI invites you and your family to discuss joining our study, in order to help us learn more about this disease.


The purpose of the study is to:

  • Find the gene or genes that cause this type of leukemia to occur in families.
  • Describe the clinical features of familial CLL.
  • Explore whether families prone to familial CLL are also at greater risk of other types of leukemia or cancer.
  • Identify biomarkers or markers that predict risk in family members.

Who is Eligible?

To participate, a family must have one of the following:

  • Two or more living individuals in the family with a history of CLL.
  • Parents, siblings and adult children of affected family members, along with other blood relatives who are genetically linked, may also join.
  • Spouses of affected family members are welcome to participate if their children (generally aged 35 and over) are participating.
  • We may consider families in which one family member has CLL, and one or more close relatives have a related blood or lymph cancer such as Non-Hodgkin Lymphoma, Hodgkin Lymphoma, or Waldenström's Macroglobulinemia.

Participating in Research

Those who join the study will be asked to:

  • Provide a blood sample or cells rinsed from the inside of the cheek for genetic studies.
  • Provide personal and medical history and family history information.
  • Give consent to obtain medical records for cancer and related conditions.

Since the genes that increase the risk of this type of familial cancer have not yet been discovered, clinical genetic testing is not part of this study. If our research finds one of these important genes, then interested individuals may be able to have formal genetic testing, either as part of this study or through an additional study.

Some participants will be offered the opportunity to visit the Clinical Center in Bethesda Maryland at no cost to them for more detailed clinical, genetic and laboratory studies aimed at finding other factors that contribute to risk among family members.

Although treatment is not a part of this study, treatment options will be discussed with participants. NCI will provide assistance in establishing care with appropriate physicians as needed. Study participants remain under the care of their primary doctors while participating in this study.

Continuing Contact

Participants and families will be asked periodically to complete a follow-up form in order to update medical and family information.

Participants are encouraged to contact the Familial CLL Team with questions or family news.

Information that would change a patient's clinical status, such as the results of routine clinical studies, will be shared with participants.

Other Details:


NCI is required by Federal Law not to reveal information that is collected from study participants to anyone other than persons directly involved in the study. No personal identifying information will be released or published.

Participants are asked if they would like us to send their health care providers a copy of the clinical findings (physical exam, routine blood work) from their visit to NIH.


All study related medical expenses and travel costs to the NIH Clinical Center for participants are paid by NCI.

For More Information

If you are interested in more information about our Familial CLL study, please contact the research team by phone at 800-518-8474 or by email at For information about familial CLL research, please contact Dr. Douglas Stewart.