Chronic Lymphocytic Leukemia (CLL) and small lymphocytic lymphoma (SLL) are basically the same diseases with different manifestations. When the disease primarily affects the node, it is labeled SLL. When it affects the bone marrow, it is labeled CLL.

CLL is diagnosed when there is absolute lymphocytosis (Monoclonal lymphocytes exceeding 5000/mm3) for three months or more. The bone marrow has usually greater than 30% monoclonal lymphocytes.

Monoclonal B lymphocytosis is a precursor form of CLL. It is defined by monoclonal B cell lymphocytosis that is usually less than 5000/mm3, the affected lymph nodes are smaller than 1.5 cm, without anemia or thrombocytopenia.

Staging Systems for Chronic Lymphocytic Leukemia (CLL) is based on the revised Rai (United States) and Binet (Europe) staging systems:

• Low risk (previously, it was called stage 0):

  • Absolute Lymphocytosis, (lymphocyte counts in peripheral blood do not exceed 15,000/mcL and bone marrow has greater than 40% lymphocytes.
• Intermediate risk (previously called stages I and II):
  • Lymphocytosis as mentioned in low-risk criteria with lymphadenopathy at any site, enlarged spleen, liver, or both.
• High risk (previously called stages III and IV):
  • Lymphocytosis as mentioned in low-risk and intermediate-risk criteria (lymphadenopathy, hepatomegaly, splenomegaly, or both) with anemia (hemoglobin level < 11.0 g/dL or hematocrit < 33%) or platelet counts less than 100,000/mcl)

Binet staging system (Europe)

• Stage A:
  • Hemoglobin ≥ 10 g/dL,
  • platelets ≥ 100,000/mm3, and
  • < 3 enlarged areas
• Stage B:
  • Hemoglobin ≥ 10 g/dL,
  • platelets ≥ 100,000/mm3, and
  • ≥ 3 enlarged areas
• Stage C:
  • Hemoglobin < 10 g/dL,
  • platelets < 100,000/mm3, and
  • any number of enlarged areas

Treatment regimens that are being used worldwide include:

• Fludarabine, cyclophosphamide, and rituximab (FCR)
• Pentostatin, cyclophosphamide, and rituximab (PCR)
• Fludarabine, cyclophosphamide, and mitoxantrone (FCM)
• Cyclophosphamide, vincristine, and prednisone (CVP)
• Cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP)