CLL is one of the most common forms of leukemia in adults. One kind of CLL [early stage low and intermediate risk (described later)] grows very slowly and rarely needs to be treated. People with this type of CLL survive an average of 15 years or more. The other kind of CLL (high risk) grows faster and is more serious. People with this kind of CLL live an average of about 8 years.
There is also Hairy Cell Leukemia (HCL) which tends to progress slowly. Most HCL are slow growing and only account for 2% of all leukemias. The cells are a type of B lymphocyte but are different from those of CLL. There are differences in treatment and symptoms.
It is estimated that in 2012 about 16,060 people in the US will develop CLL. There will be about 4,580 deaths from CLL. CLL accounts for about 1/3 of all leukemias. The average age at diagnosis is 72, and the disease is twice as common in men as women and is rarely seen in children.
In CLL, the body produces large numbers of white blood cells (lymphocytes). These cells cannot fight infection well. The changes in the diseased cells prevent them from maturing. The cells lose their ability to mature and have a much longer lifespan than normal lymphocytes. Over time their large numbers fill up the bone marrow and the tissues of the lymphatic system, displacing the normal red and white blood cells and platelets. They interfere with other immune system functions.
Risk factors can include an inherited or genetic trait, or exposure to toxins in the environment. It is unlikely that a person who has one of these known risk factors develops leukemia. It is known that if you have a first degree relative – parent, child, sibling- with CLL you have a 2-4 fold increased risk of developing CLL. CLL may also be linked to exposure with Agent Orange, a chemical used during the Vietnam War.
A person may have no symptoms for the first few years when they develop CLL. It may be discovered when a person has a routine check-up with a blood test. However, as the number of diseased cells increase, they start to interfere with the normal functioning of the body. At that time symptoms will slowly develop.
These symptoms may include:
In order to diagnose leukemia your doctor will ask you questions about your past health and symptoms. Your doctor will do a physical exam, will look for swollen lymph nodes and check to see if your liver or spleen is larger than normal. Blood tests will be ordered to check to see if your white blood cells are high and your other blood cells levels are low. If you have abnormal blood tests then your doctor may do a bone marrow biopsy. This test will look at the inside of your bone. Flow cytometry might be used to look for certain substances on the outside surface of the cells that help identify what types of cells they are. Imaging such as a CT scan, MRI or ultrasound can find out if other organs such as the lung, liver, spleen, lymph nodes, brain and kidneys have been affected as well.
There are two different systems for staging CLL. The Rai system is used more often in the US. The Binet system is used more often in Europe.
The Rai system divides CLL into 5 stages.
When determining treatment Rai stages are separated into low, intermediate and high risk.
Along with stage, other factors which are not favorable include advanced age, male, deletions of certain chromosomes, increased proportion of large or atypical lymphocytes, and some others are sometimes taken into account when discussing treatment options. On the other hand, there are factors which may be helpful. Some of those include a non-diffuse pattern of bone marrow involvement (less widespread replacement of normal marrow by leukemia) , deletion of part of chromosome 13, CLL cells with a mutated gene, and some others. These factors can help predict longer survival.
Treatments for CLL are based on both the stage and the symptoms of the patient. A large group of CLL patients have low grade disease which may not benefit from treatment. If a patient has complications related to CLL, or more advanced disease, they often benefit from treatment.
In general, treatment would be based on the following:
Treatments can include chemotherapy which uses powerful medicines to kill cancer cells. This is the most often used treatment for most types of leukemia. The primary chemotherapy plan is to combine chlorambucil (Lukeran®) or cyclophosphamide (Cytoxan®), plus a corticosteroid such as prednisone or prednisolone. Using a corticosteroid has the benefit of suppressing some related autoimmune diseases, such as immunohemolytic anemia or immune mediated thrombocytopenia. A newer drug called bendamustine (Treanda®) may be used. In cases where there is resistance to treatment, drugs that are in a certain group called purine analogs (chemical compounds having a structure similar to that of another but differing from it in respect to a certain component that inhibits DNA synthesis) may be used such as fludarabine Fludara®, pentostatin (Nipent®), or cladribine (2-CdA, Leustatin®). Sometimes other drugs include doxorubicin (Adriamycin®), methotrexate, oxaliplatin, vincristine (Oncovin®), etoposide (VP-16) and cytarabine (ara-C) are used.
Monoclonal antibodies are man-made proteins that are carefully engineered to attach to specific defects in cancer cells. Monoclonal antibodies mimic the antibodies your body naturally produces as part of your immune system's response to germs, vaccines and other invaders so they can be used to help the patient’s immune system reach and destroy cancer cells. There are several that can be used to treat CLL. Rituximab (Rituxan®) is a monoclonal antibody that is most often given along with chemotherapy, either as part of the initial treatment or as part of a second-line treatment, but sometimes by itself. Campath® (Alemtuzumab) is a monoclonal antibody mainly used for patients who are no longer responding to treatment.
Arzerra® (Ofatumumab) can be used for patients with CLL who are no longer responding to other treatments such as chemotherapy or alemtuzumab.
Younger patients may consider an allogeneic or autologous bone marrow transplant.
Chronic leukemia can rarely be cured, but the treatments can help control the disease. If you have CLL, you may not need to be treated until you have symptoms. But CML will usually be treated right away.
Radiation therapy uses high dose x-rays to destroy cancer cells and shrink swollen lymph nodes or an enlarged spleen. It may also be used before getting a stem cell transplant.
Sometimes there are very high numbers of leukemia cells in the blood that cause a problem with normal circulation. Leukopharesis, which is a process that removes white blood cells, can be used to lower the blood counts very rapidly, which may help until the chemotherapy has a chance to work.
Patients with Hairy cell leukemia are treated once symptoms appear. They may be followed every few months for progression to see if their blood counts decrease, or they get recurrent infections or an enlarged spleen or lymph nodes. At that time treatment would be with either cladribine (2-CdA) or pentostatin. Up to 80-90% of patients respond to those drugs, and the response can last more than 5 years. If the HCL recurs then many will respond to a second line treatment. Rituximab can also be used. HCL is a fairly rare disease.
Stem cell transplants can help rebuild the supply of normal blood cells and boost your immune system. Before getting a transplant, radiation or chemotherapy may be given to destroy cells in your bone marrow and make room for the new stem cells. Or it can be given to weaken your immune system so the new stem cells can grow.
Clinical trials may be an option for some people. Clinical trials are research projects that test new medicines and treatments. Many people with leukemia take part in clinical trials.