Types of Leukaemia Inverness
Types of Leukaemia
Do you know Chronic Lymphocytic Leukaemia, and what is the plan to treat it? Isn't leukaemia a serious condition that needs treatment?
Leukaemia is cancer of the bone marrow and blood that causes an unrestrained production of a certain type of white blood cell. Although it is not known what sets off leukaemia, we do know that leukaemia is usually caused by a mutation in the genes of the patient.
Chronic Lymphocytic Leukaemia (CLL) is a specific type of leukaemia that affects lymphocytes, a type of white blood cell that forms in the bone marrow, develops in the lymph nodes and functions to fight certain types of infections. This is termed a chronic leukaemia because it may be indolent (slowly or non-progressive) for years, especially in its early stages.
CLL more commonly affects older people, with an average age at diagnosis of 65 to 68.
The abnormal lymphocytes of CLL do not work effectively and live much longer than normal cells. They can accumulate in the blood and in certain organs (usually the lymph nodes, spleen or liver) causing complications. Furthermore, their proliferation in the bone marrow can "crowd out" normal cells, leading to an insufficient number of red blood cells (anaemia), platelets (causing easier bleeding) or normal white blood cells (predisposing to infection).
- Unsurprisingly, the symptoms of CLL can include:
- Enlarged lymph nodes, spleen and/or liver (the latter two can lead to abdominal discomfort)
- Fatigue (due to anaemia) and weight loss
- Abnormal bleeding even after minor injuries
- Infections (like pneumonia), fever, chills and night sweats
However, most people initially diagnosed with CLL have minimal or no symptoms, the diagnosis being suspected when an abnormally high white blood cell count is noted on a blood test done for other reasons or for an annual evaluation.
CLL patients can have many possible complications, some life threatening. Aside from the consequences of infections or bleeding, some CLL patients "transition" into a rapidly progressive acute leukaemia.
A blood test that measures the amount and type of white blood cells is typically the first step in diagnosing CLL. After this, more specialized tests - such as flow cytometry or immunophenotyping - may be done. More recently, fluorescence in situ hybridization has been developed to define specific chromosomal mutations. Other tests may be indicated as well.
Once CLL is diagnosed, the extent of the disease must be determined. This is called "staging," and the "stage" of the leukaemia will be used to estimate the prognosis and to determine the best treatment. There are several staging systems, and new research based on the specific mutations identified promises improvements in the future. For illustration purposes I will discuss the Rai staging system which has been around for over 25 years.
Low-risk patients in the Rai system have elevated white blood cells but no other disease manifestations. The average life expectancy without treatment for these patients is over 12.5 years. Moreover, some studies have shown that treatment of low-risk patients does not improve survival, although it may have significant side effects and toxicity.
Intermittent-risk patients also have enlarged lymph nodes and/or enlarged spleen/liver. These patients have an average life expectancy of over 8.5 years.
High-risk patients have low blood counts (white blood cells, platelets or red blood cells), and have an average life expectancy of 1.5 to 4 years.
Therefore, it is easy to see why low-risk patients may be best served by a "wait and watch" strategy. However, people with intermediate or advanced-stage disease may need to begin treatment soon after the diagnosis is made.
Treatment options include chemotherapy, targeted drug therapy (medications designed to bind to proteins on the cancer cells, targeting and killing them), or bone marrow stem transplant (where all the blood cell lines are destroyed using chemotherapy and possibly radiation therapy, then stem cells are re-introduced to allow repopulation of the bone marrow and blood by normal, healthy cells).
If you or a loved one is diagnosed with CLL, waiting and watching may be the most appropriate treatment strategy. It is important that the patient is closely followed by an experienced physician. New evaluation and treatment options are being developed; for example, some very recent work using antibodies to block a stem cell factor overproduced by leukaemia cells has shown promise in a mouse model.
Stephanie Copithorne contributed to this column. Jeff Hersh, Ph.D., M.D., F.A.A.P., F.A.C.P., F.A.A.E.P., can be reached at DrHersh@juno.com.author: Dr. Jeff Hersh