Chronic lymphocytic leukemia and small lymphocytic lymphoma

Chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) are often considered different versions of the same disease because they are very similar. They both start in B cells, may be slow growing (indolent) and usually occur in older adults. They differ in where the lymphoma cells are found. In CLL, the lymphoma cells are mainly found in the blood and bone marrow. In SLL, the lymphoma cells are mainly found in the lymph nodes and spleen.

Sometimes CLL/SLL will change into a fast-growing (aggressive) type of NHL (when this happens, it is called Richter’s syndrome or a Richter transformation). In rare cases, CLL/SLL can change into B-cell prolymphocytic leukemia (B-PLL).


Many people with CLL/SLL don’t have symptoms that cause problems. Sometimes they have low red blood cell counts (called anemia) and low platelet counts (called thrombocytopenia) because the immune system starts to destroy some of these cells. The spleen and liver may become larger than normal and leukemia/lymphoma cells may spread to organs or tissues other than the lymph nodes (called extranodal spread).


The treatments offered for CLL/SLL depend on whether the disease is causing any symptoms or progressing. You may be offered one or more of the following treatments:

Watchful waiting

Many people with CLL/SLL who don’t have symptoms or problems may be offered watchful waiting (also called active surveillance). The healthcare team will carefully monitor the person with CLL/SLL and start treatment when symptoms appear or there are signs that the CLL/SLL is progressing.


Chemotherapy may be a treatment option for people with CLL/SLL.

CLL/SLL is often treated with one of the following combinations of chemotherapy drugs:

  • CVP – cyclophosphamide (Cytoxan, Procytox), vincristine (Oncovin) and prednisone
  • FC – fludarabine and cyclophosphamide

The following chemotherapy drugs may be given alone:

  • chlorambucil (Leukeran)
  • fludarabine (Fludara)
  • bendamustine (Treanda)

Bendamustine may be used if CLL/SLL comes back (recurs).

Steroids, such as prednisone or dexamethasone (Decadron, Dexasone), may be used alone to treat immune complications such as autoimmune hemolytic anemia or low platelet counts that develops in some people with CLL/SLL.

Radiation therapy

External beam radiation therapy may be a treatment option for CLL/SLL. It may be given to the parts of the body that contain lymphoma cells, such as certain groups of lymph nodes or the spleen. It is used to control symptoms that develop when the lymph nodes or spleen are larger than normal. Radiation therapy may also be given in addition to chemotherapy.

Targeted therapy

Targeted therapy uses drugs to target specific molecules (such as proteins) on the surface of cancer cells. These molecules help send signals that tell cells to grow or divide. By targeting these molecules, the drugs stop the growth and spread of cancer cells while limiting harm to normal cells.

Rituximab (Rituxan) is the most common targeted therapy used to treat NHL. It is often used in combination with chemotherapy to treat CLL/SLL.

Other targeted therapy that may be offered to people with CLL/SLL are alemtuzumab (Campath), ibrutinib (Imbruvica), obinutuzumab (Gazyva) or ofatumumab (Arzerra).

Stem cell transplant

A stem cell transplant may be an option for some younger people with CLL/SLL that no longer responds to treatment (called refractory disease).

Expert review and references

  • American Cancer Society. Non-Hodgkin Lymphoma. 2014:
  • American Society of Clinical Oncology . Lymphoma Non-Hodgkin Overview . 2014 :
  • Freedman AS, Jacobson CA, Mauch P, Aster JC . Non-Hodgkin lymphoma. DeVita VT Jr, Lawrence TS, & Rosenberg SA. Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 103:1552-1583.
  • Manson SD & Porter C . Lymphomas. Yarbro, CH, Wujcki D, & Holmes Gobel B (eds.). Cancer Nursing: Principles and Practice. 7th ed. Sudbury, MA: Jones and Bartlett; 2011: 60: pp. 1458-1512.
  • Medeiros L J . Pathology of non-Hodgkin's and Hodgkin's lymphomas. Wiernik PH, Goldman JM, Dutcher JP, Kyle RA (eds.). Neoplastic Diseases of the Blood. 5th ed. Springer; 2013: 42: 867-918.

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