Chronic lymphocytic leukemia (CLL) may cause complications such as those outlined below.
Infection is a common complication for people with CLL. Because of the high risk of infections, immediate vaccination for pneumococcal pneumonia with Prevnar 13® and a yearly flu vaccine is recommended. CLL patients do not respond well to vaccines due to their immune system depression. CLL patients should never receive live vaccines (such as the shingles vaccine).
A higher risk of infection is caused by
- The inability of the person's CLL cells to make antibodies needed to fight infections
- The effect of chemotherapy, which causes reduced cell counts for certain infection-fighting white cells in the blood, specifically neutrophils and monocytes.
Antibiotic therapy is usually required to treat bacterial or fungal infections during the course of the disease. People who get recurrent infections may also receive injections of immunoglobulin (gamma globulin) on a regular basis to correct the immune deficiency. While immunoglobulin is expensive, it does have benefit in decreasing the frequency of infections in CLL patients with low levels of this in the blood.
CLL-related low blood counts are often efficiently corrected by CLL therapy. However, the use of white cell growth factors may benefit patients who experience prolonged low white cell counts after treatment. Examples of white cell growth factors are
- Granulocyte-colony stimulating factor (G-CSF) (filgrastim [Neupogen®] or pegfilgrastim [Neulasta®]) that can increase the number of neutrophils
- Granulocyte-macrophage colony-stimulating growth factor (GM-CSF) (sargramostim [Leukine®]) that can increase the number of neutrophils and monocytes.
Anemia (low numbers of red cells) is a common side effect of chemotherapy. Some people with CLL may need blood transfusions.
In about 3 to 5 percent of people with CLL, the disease transforms into an aggressive lymphoma because of a change in the characteristics of the CLL cells. This is much more common in IGHV-unmutated CLL. This pattern is referred to as a "Richter transformation" or "large cell transformation." People with this type of CLL may have significantly enlarged lymph nodes, and may have fevers and weight loss. Tumours of lymphocytes may also develop in parts of the body other than the lymph nodes. Richter transformation is treated with aggressive chemotherapy and reduced-intensity allogeneic transplantation if feasible. Outcome for patients with Richter transformation is generally poor unless it is diagnosed prior to receiving a lot of treatment for CLL.
About 15 percent of people with CLL have leukemia cells that are a mix of lymphocytes and another type of white cell, called a "prolymphocyte." Most people with this type of CLL follow a similar course to that of other people with CLL. However, for a relatively small subset of patients with this type of CLL, the blood cells may become mainly composed of prolymphocytes; the spleen may enlarge further, and the disease may become less responsive to treatment. In these cases, individuals are encouraged to talk to their doctors about the potential benefits of treatment in a clinical trial.
Autoimmune Hemolytic Anemia
Some people with CLL produce a type of antibody that works against their own cells. These "autoantibodies" are usually directed against the patient's red cells and causes them to be removed rapidly from the blood. This condition, called "autoimmune hemolytic anemia," can worsen the effects of already low red cell counts. The "antiglobulin test" or "Coombs' test" is used to identify the autoantibodies. Less often, the antibody works against the platelets. This condition, called "immune thrombocytopenia" results in significantly decreased platelet counts. The drugs prednisone, Rituxan and cyclosporine are sometimes used to treat autoimmune hemolytic anemia and immune thrombocytopenia.
People with CLL have a higher risk than the general population of developing a second cancer. The cancers that tend to occur most often include:
- Soft tissue sarcoma
- Colorectal cancer
- Lung cancer
- Squamous cell skin cancer
- Basal cell carcinoma, with a high recurrence rate
CLL patients are also at higher risk for other blood cancers and disorders such as:
This complication is more common after treatment with fludarabine and cyclophosphamide (FC or FCR). Further evaluation is needed to determine whether treatment with fludarabine may increase the risk of second solid tumour cancers. It is important to follow up with your oncologist on a regular basis.