In general, cure and remission rates of leukemia continue to improve for both children and adults.
Specific treatment depends on the type of leukemia, severity, and symptoms. The goals of treatment are to address the cell shortages that are causing symptoms, induce remission, and, if possible, kill all of the abnormal white blood cells, allowing normal cells to develop and restore normal bone marrow function. Since treatment options are in constant flux, and changing rapidly for some kinds of leukemias, it is important to make individual decisions with a healthcare provider familiar with the most recent research.
Standard leukemia treatment may include chemotherapy drugs and sometimes radiation, both to kill cells and to relieve pain. If leukemia cells have migrated into the cerebrospinal fluid, chemotherapy drugs that are injected directly into the spinal fluid may be required. Red blood cell and/or platelet transfusions and antibiotic therapy may also be necessary. In chronic leukemias, surgery can be required to remove the spleen if it is too swollen or painful.
In some cases, it may be necessary to restore healthy bone marrow or stem cells with transplants. Bone marrow samples may be taken from the affected person, "cleaned" of abnormal cells, and frozen to be reintroduced into the same person following treatment, known as an autologous bone marrow transplant, or rescue transplant. Stem cells or bone marrow transplants from a compatible donor are known as allogeneic transplants. Bone marrow transplants may be considered when other treatment regimens have failed to push the leukemia into remission, or when the leukemia has recurred.
Treatment and prognosis of leukemia depend upon the type of disease. For example, people with CLL do not need chemotherapy until they show symptoms or their red blood cells or platelet numbers decrease. However, allogenic stem cell transplants are the only known potential cure for CLL. Typical treatment for ALL includes long-term chemotherapy. People with AML may need several types of treatment, as soon as possible after diagnosis. This may include chemotherapy followed by a stem cell transplant. Long-term remission can be achieved in people with CML with drugs that are called tyrosine kinase inhibitors (TKI).
In addition to these treatments, researchers are continuing to investigate new types of therapies to achieve remission and prolong the lives of people with leukemia. A better understanding of how changes in DNA lead to abnormal blood cells is helping researchers develop cancer drugs that inhibit or target specific proteins associated with certain cancers. Tests that detect these genetic abnormalities help health practitioners decide when a person is likely to benefit from these targeted cancer therapies.
For example, people with CML have a mutation in the BCR-ABL gene sequence, found in an abnormal chromosome, known as the Philadelphia chromosome. Abnormalities in that chromosome lead to the production of an enzyme, tyrosine kinase, which causes uncontrolled growth of leukemia cells. Now, people with CML are generally treated with a TKI, like Imatinib, to impede the growth of cancer cells caused by the Philadelphia chromosome. Tyrosine kinase inhibitors are also used to treat ALL and are being investigated in other types of leukemias, like the drug Ibrutinib for CLL.
There are a number of other targeted gene therapies available for leukemia, as well as clinical trials for new FDA-approved therapies. Targeted therapies are promising because they are specifically tailored to cancer cells, they are less harmful to normal cells compared to conventional chemotherapy, and thus may be more effective while having less severe side effects. New therapies are being studied alone, in combination, or alongside traditional therapies. Targeted cancer therapies are not without limitations, such as the potential for cancer cells to develop resistance to them. For that reason, targeted therapies may work best in combination with more standard treatments, not as a replacement for them.