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Non-Hodgkin lymphoma

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Chronic lymphocytic leukemia and small lymphocytic lymphoma

Chronic lymphocytic leukemia is a type of leukemia that mostly affects B-cell lymphocytes. Small lymphocytic lymphoma is also a cancer of the B-cell lymphocytes. B-cell chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) are very similar diseases. They only differ in where the cancer occurs.

  • With CLL, the abnormal lymphocytes mainly affect the blood and bone marrow.
  • With SLL, the abnormal lymphocytes mainly affect the lymph nodes.

CLL and SLL are included together in one category of B-cell lymphomas in the World Health Organization (WHO) classification. CLL and SLL account for close to 7% of all cases of NHL.

CLL and SLL are both slow growing (indolent). They both usually occur in older adults.

Many people with CLL and SLL may not have symptoms that cause problems. Sometimes they have anemiaanemiaA reduction in the number of healthy red blood cells. and low platelet counts (thrombocytopenia) because their immune system starts to destroy some of their red blood cells and platelets.

Sometimes CLL and SLL change (transform) into a more aggressive type of lymphoma, a large cell lymphoma called Richter’s syndrome.


Treatment for CLL and SLL depends on the stage and if the disease is causing any symptoms or problems.

Watchful waiting

Many people with CLL or SLL may be closely monitored if the lymphoma isn’t causing any symptoms or problems. Treatment is started when symptoms appear or there are signs that the lymphoma is progressing.


Chemotherapy may be a treatment option for people with CLL or SLL. Single chemotherapy drugs may be used to treat CLL and SLL, including:

  • chlorambucil (Leukeran)
  • fludarabine (Fludara)

Many people with CLL or SLL will receive a combination of chemotherapy drugs, the same combinations that are used for other lymphomas:

  • CVP – cyclophosphamide (Cytoxan, Procytox), vincristine (Oncovin) and prednisone (Deltasone)
  • CHOP – cyclophosphamide, doxorubicin (Adriamycin), vincristine and prednisone
  • fludarabine and cyclophosphamide
  • fludarabine, cyclophosphamide and mitoxantrone (Novantrone)

A drug called bendamustine (Treanda) is similar to the chemotherapy drug mechlorethamine (nitrogen mustard, Mustargen). It may also be used to treat people with CLL who have relapsed after initial therapy.

Radiation therapy

External beam radiation therapy may also be an option for some people with CLL or SLL. It may be given to areas where cancer cells are found, such as some lymph node areas or the spleen.

Radiation therapy may also be given in addition to chemotherapy.

Biological therapy

Monoclonal antibodies are a type of biological therapy that is effective in treating certain types of NHL. Rituximab (Rituxan) is often used in combination with chemotherapy to treat CLL and SLL.

Alemtuzumab (Campath) is a monoclonal antibody that may be offered to some people with CLL or SLL if they have been treated with fludarabine (Fludara) and it is no longer working.

Stem cell transplant

A stem cell transplant (SCT) may be an option for some younger people with CLL or SLL who are no longer responding to treatment (refractory).

For more detailed information on specific drugs, go to sources of drug information.


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