CLL is the most common type of leukemia diagnosed in adults with an estimated 14,500 new cases a year. It occurs somewhat more frequently in men than in women. About 90% of people with CLL are over the age of 50 when they are diagnosed. CLL is rare in young adults and almost never occurs in children. The overall five year survival rate for CLL is about 80%.
No one knows what causes CLL. Some of the factors that increase a person's risk of getting other types of leukemia, such as exposure to radiation and certain chemicals, do NOT appear to increase the risk of CLL. Having a relative who has CLL may slightly increase the risk of CLL. People of Russian and European descent have a higher incidence of one type of CLL, while people of Asian heritage rarely get CLL. The reason for these differences is not known. Soldiers and civilians exposed to Agent Orange during the Vietnam War also have a higher incidence of CLL.
Many people with CLL don't have any symptoms of their disease. It is often discovered as a result of a blood test done for another reason. Symptoms include swelling of the lymph nodes in the neck, under the arm or in the groin; repeated fevers and infections; abnormal bleeding; weight loss, shortness of breath and a feeling of fullness in upper left part of the abdomen.
A blood test and a thorough physical and medical history are the first steps to diagnosing CLL. If a blood test shows a very high number of white blood cells, the doctor may suspect CLL or another form of leukemia. Some patients with CLL are also anemic because the large number of abnormal lymphocytes crowd out normal red blood cells and platelet.
In some cases, the diagnosis of CLL can be made from blood tests alone, but in others a bone marrow biopsy is needed to confirm the diagnosis or help determine the prognosis. Blood cells are produced and stored in the bone marrow. This test involved removing a sample of the bone marrow, usually from the hipbone, for examination under the microscope.
CLL cells have distinctive markers on their surfaces. Doctors use techniques known as flow cytometry and cytochemistry to identify these markers. This is important to distinguish CLL from other types of leukemia that involve lymphocytes.
In some cases, patients will also undergo imaging tests, such as CT scans or MRI to determine the extent of the disease. Since CLL is a blood cancer, the cells are carried throughout the body, and for this reason, it is not always necessary to do x-rays or scans.
Staging is a way of describing the exact type and extent of a cancer. Accurate staging is very important in determining the best approach to treatment and assessing the prognosis. Staging for CLL is done on a scale of 0 to IV, with 0 being the least advanced and IV the most advanced.
Briefly, the stages for CLL are:
CLL Patients are also divided in risk groups according to the stage of their disease. Stage 0 patients are in the low risk group; stage I and II patients in the intermediate risk group; and stage III and IV patients in the high risk group.
If CLL comes back after treatment, it is known as recurrent CLL.
Note: European doctors use a slightly different staging system for CLL.
Knowing the patient's stage, risk level and overall level of health is important to determining the best treatment. CLL can be controlled for long periods of time, but it is not a curable disease. The goal is to achieve a long term remission--a period of time in which the signs and symptoms of the disease either completely or partially disappear.
For as many as 50% of newly diagnosed CLL patients, there is no need to treat the cancer right away. These are patients with early stage disease and low risk levels. This is known as active surveillance or watch and wait. It means that doctors will monitor the patient very closely and if the disease begins to get worse, then start treatment. Some patients don't progress or develop symptoms for decades, or at all, and will never need treatment.
For patients with more advanced disease or whose CLL progresses, doctors use a combination of chemotherapy and targeted agents. There are several combinations that are effective in controlling CLL. The exact nature of the treatment depends on the stage of the disease, symptoms, and the patient's overall health.
Targeted therapies are newer approaches to treating cancer. The most common targeted therapy for CLL binds to a specific protein on the abnormal lymphocytes, killing some of them and making others more vulnerable to chemotherapy. There are a number of clinical trials underway to develop new targeted therapies and combinations of therapies, especially treatments for CLL which has recurred or not responded to treatment.
The goal of treatment for CLL is to get the patient into a remission. In a complete remission, all signs and symptoms of the disease disappear. In a partial remission, there is a response to the treatment, but some cancer remains. Many CLL patients achieve partial remissions in which they have normal blood counts, feel good, and do not have enlarged lymph nodes or spleens, but often still have CLL in their bone marrow. These patients can often do well for long periods of time. There is research underway both to develop better treatments for CLL that will result in longer lasting remissions and to be able to define changes in the cell's DNA that are specific to CLL. This would allow much more precise measurement of when remissions occur and how long they last.
In some cases, the CLL does not respond well to treatment and continues to get worse, known as refractory disease. In others, the initial response to treatment is good but the CLL comes back, known as recurrent disease. When this happens, doctors can change the combination of drugs that is being administered. In some cases, refractory or recurrent CLL patients are candidates for a stem cell transplant that replaces the diseased bone marrow with healthy cells from a donor or the patient. Patients whose CLL is not responding to treatment should ask about clinical trials for CLL which are studying better methods of treating the disease.
CLL is not curable but it is a form of leukemia that people can often live with for many years. In some patients, it is slow growing and does not cause symptoms. Those patients often do not need active treatments. For patients with more advanced disease, there are a number of effective treatment options. Research is underway to find new drug and targeted therapies as well as to identify specific genetic changes that occur with CLL. That could lead to better ways of knowing who needs active treatmet, as well as possible new approaches to therapies. CLL is often a chronic disease so controlling the symptoms and helping people lead active, normal lives is very important. Cancer Bites.
ALL is one of four major types of leukemia.