Physicians devise a course of treatment for each CLL patient based on the stage and symptoms of the disease and the patient’s age and overall health.
To date, no treatment approach is considered a cure for CLL. Current treatment strategies are designed to slow the progression of disease and to alleviate symptoms. Fortunately, many patients do not develop significant symptoms and do not require treatment for years after the disease is discovered. Because CLL can develop very slowly, many patients die from other causes before their disease becomes symptomatic.
Early-Stage, Low-Risk CLL
In patients who have early-stage, low-risk CLL (Rai stage 0), physicians usually defer treatment until signs of the disease develop, which can happen years after the initial diagnosis.
Intermediate and High-Risk CLL
Physicians may treat patients with intermediate (Rai stages I or II) or high-risk CLL (Rai stages III and IV) whose symptoms indicate that treatment is needed, with either a single agent or a combination chemotherapy, which could include a mix of the following agents: pentostatin, fludarabine, rituximab, cyclophosphamide, and prednisone.
Physicians in rare cases use localized radiation therapy — treatment with high-energy rays that destroy cancer cells — as a palliative treatment for CLL to control enlarged lymph nodes or an enlarged spleen.
Stem Cell Transplant
A stem cell transplant is an option for some CLL patients. Doctors obtain stem cells — blood-forming cells — by filtering them from the patient’s or a donor’s bloodstream, then sometimes freezing them. The patient is treated with a high-dose course of chemotherapy, which destroys the cancer cells but also damages the patient’s own blood-forming cells. Doctors then administer or transplant the harvested stem cells to the patient to help rebuild his or her immune system. When patients receive their own stem cells back, the procedure is called an autologous stem cell infusion. If the stem cells are not the patient’s but a donor’s, the procedure is called an allogeneic stem cell transplant.
In some cases, CLL causes a patient’s immune system to attack its own cells. This can result in a range of autoimmune conditions that are often treated with corticosteroids such as prednisone.
Another complication of CLL is Richter syndrome (or Richter transformation). In patients with this condition, CLL undergoes a transformation into a high-grade or aggressive non-Hodgkin’s lymphoma (NHL). These patients are treated for NHL.
New, highly sensitive laboratory tests can now probe for minimal residual disease — the very few leukemia cells that may remain in the body after treatment ends — in patients with specific types of leukemia. With the information derived from such tests, physicians can chart further treatment options for leukemia patients.
Researchers at Memorial Sloan Kettering continue to develop new agents for cancer treatment, and to test new treatment approaches in our clinical trials. Relying in part on the information that is emerging about the genetic basis of leukemia, investigators are pursuing a variety of strategies to control the disease — approaches that can kill tumor cells directly, inhibit the body’s production of substances that promote their growth, or enhance the immune response against leukemic cells.
Drugs used in chemotherapy work in different ways to stop tumor cells from dividing and to prompt them to undergo programmed cell death, or apoptosis. Physicians usually combine two or more agents in a course of treatment in an effort to kill as many tumor cells as possible. It is not yet known which regimen of combination chemotherapy is most effective for CLL, so clinical trials are underway to compare the effectiveness of various combinations of chemotherapeutic agents.
Monoclonal antibodies are genetically engineered proteins designed to target specific proteins called antigens located on the surface of tumor cells. Researchers at Memorial Sloan Kettering are testing the monoclonal antibody rituximab, in combination with other agents, to determine its most effective use against CLL. Rituximab attaches to the CD20 receptor found on the surface of many types of lymphocytic leukemia cells and in some patients causes the diseased cells to die or to be cleared from the body.
T cells are a form of white blood cell. Researchers at Memorial Sloan Kettering are working to produce T cells that will recognize and attack a patient’s cancer cells. To do this, they extract some of the patient’s own T cells, introduce a gene that allows these cells to recognize a protein on the surface of the leukemia cells, and grow the altered cells in culture. The new T cells should be able to recognize the antigens as foreign and should multiply in order to attack. Investigators then administer the “engineered” T cells back into the patient so that they will seek out and destroy the cancer cells.
Researchers at Memorial Sloan Kettering are evaluating new drugs to treat CLL that could prove to be active and potentially curative for this disease. In addition, researchers here are studying treatments that have fewer side effects than current regimens for use in older patients with CLL. More than half of patients with CLL are 65 or older, and with increasing age, patients are often less able to tolerate the side effects of currently available treatments.
People with CLL are likely to see their physician often to monitor the disease and to determine if it is progressing. These check-ups may include a physical exam, blood tests, bone marrow aspirates, biopsies, and radiographic studies.