Also known as ALL, it is a type of blood cancer. It is the least common type of leukemia in adults.
ALL is a type of leukemia that begins with white blood cells in the bone marrow , the soft inner part of the bones.
It develops from cells called lymphocytes , a type of white blood cell central to the immune system, or from lymphoblasts, an immature type of lymphocyte.
Acute lymphoblastic leukemia invades the blood and can spread throughout the body to other organs, such as the liver, spleen, and lymph nodes.
However, it does not normally cause tumors, as many types of cancer do.
It is an acute type of leukemia, which means that it can progress rapidly. Without treatment, it can be fatal within a few months.
The prognosis for acute lymphoblastic leukemia depends on a number of factors, such as:
- Age: Younger patients tend to have a better prognosis.
- Laboratory test results: The prognosis is better if you have a lower white blood cell count when the disease is diagnosed.
- The subtype of ALL that has been diagnosed (B-cell ALL or T-cell ALL).
- The presence of the chromosomal abnormality called the Philadelphia chromosome suggests a worse prognosis.
- Response to chemotherapy: The outlook is better if you have no evidence of leukemia four to five weeks after starting treatment.
Causes and Risk Factors of Acute Lymphoblastic Leukemia
For most people, the cause of ALL is unknown. For this reason, there is no exact way to prevent it.
However, there are some known risk factors for this type of leukemia. This means that these factors can increase your chances of developing acute lymphoblastic leukemia.
However, it is not yet known whether these risk factors are the actual causes of the disease. These are:
- Exposure to high levels of radiation to treat other types of cancer.
- Exposure to certain chemicals such as benzene (a solvent used in oil refineries and found in cigarette smoke), certain cleaning products, detergents, and paint removers.
- Having an inherited genetic syndrome such as Down syndrome.
- Fair-skinned people are more likely to develop acute lymphoblastic leukemia.
- Men are more likely to develop acute lymphoblastic leukemia.
Some of the symptoms of the disease can be vague and not specific only to leukemia, such as:
- Loss of appetite or weight.
- Night sweats.
Many symptoms of acute lymphoblastic leukemia are the result of a shortage of normal blood cells.
This is because the leukemia cells crowd out these normal cells in the bone marrow.
So a shortage of red blood cells can cause symptoms of anemia, including:
- Fatigue or weakness
- Short of breath.
A shortage of normal white blood cells can lead to:
- Recurring infections.
A shortage of platelets in the blood can cause symptoms such as:
- Large amount of bruising for no obvious reason.
- Frequent or severe nosebleeds, bleeding gums, or other unusual bleeding such as minor cuts.
Depending on where the leukemic cells are present, other symptoms can present themselves as:
- A belly full or swollen with leukemia cells, also in the liver or spleen.
- Enlarged lymph nodes, such as in the neck or groin, under the arms, or above the collarbone.
- Bone or joint pain
- Headache, problems with balance, vomiting, seizures, or blurred vision if the cancer has spread to the brain.
- Trouble breathing if it has spread to the chest area.
Treatment of acute lymphoblastic leukemia
ALL is really a group of related diseases and is divided into subtypes. Therefore, your treatment options depend on your subtype and other factors.
You can have more than one type of treatment. These include:
Chemotherapy: the use of anticancer drugs, usually for a couple of years.
Targeted therapy: Drugs that target specific parts of cancer cells and tend to have fewer serious side effects than chemotherapy.
Radiation therapy – the use of high-energy radiation to kill cancer cells; This is not often used for ALL, but can be used to treat leukemia in the brain or bones.
A bone marrow transplant: involves the use of high doses of chemotherapy and possibly radiation followed by a bone-forming stem cell transplant.
Stem cells usually come from a donor, or less likely, from your own bone marrow or peripheral blood.
If the patient cannot tolerate high doses of chemotherapy and radiation, lower doses can be used with a small transplant.
The treatment occurs in two parts; induction therapy and post-induction therapy. The goal of induction therapy is to achieve remission by:
- Killing as many leukemia cells as possible.
- Return blood counts to normal.
- Removing the body from the signs of the disease for a long time.
About eight to nine out of 10 adults achieve remission after treatments, but many relapse, reducing the overall cure rate from 30% to 40%.
Therefore, even with remission, post-induction therapy is needed to prevent relapse. It involves treatment cycles for two to three years.
The drugs are generally different from the drugs used in induction therapy.
The goal is to completely rid the body of leukemic cells that have not been found by common blood or marrow tests.
A form of immune cell therapy called T-cell therapy has been approved. This uses some of a patient’s immune cells, called T cells, to treat their cancer.
Doctors remove cells from the blood and add new genes to them. The new T cells are better able to find and kill cancer cells .
Currently, the drug used for therapy called tisagenlecleucel (Kymirah) is only approved for children and young adults up to 25 years of age with B-cell ALL who have not improved with other treatments.
However, scientists are working on a version of T-cell therapy for adults and for other types of cancer.