What Is Acute Lymphoblastic Leukemia (ALL)?
Acute lymphoblastic leukemia (ALL) is a cancer of the blood in which too many lymphocytes, a type of white blood cell, are produced by the bone marrow and by organs of the lymph system. The term “acute” indicates that the disease progresses rapidly.
Normally, the lymphocytes fight infection. But, in ALL, the cells are immature and overabundant. They crowd out other blood cells and may collect in the blood, bone marrow, and lymph tissue.
Acute leukemia can grow quickly and requires treatment as soon as possible after it is found. Chromosome abnormalities (extra chromosomes and structural changes in the chromosome material) are present in the majority of patients.
ALL is the most common form of childhood leukemia, with most children between the ages of two and four when the cancer is found. Despite being a common childhood cancer, about one-third of ALL cases occur in adults. According to the American Cancer Society, about 6,020 ALL cases are expected in 2014. The average person has about a one in 750 chance of developing ALL. In adults, the highest risk of developing the disease begins about age 50 and increases thereafter. Factors thought to increase the risk of developing ALL include past exposure to certain types of chemotherapy or radiation.
Symptoms of Acute Lymphoblastic Leukemia (ALL)
The following are the most common symptoms of acute lymphoblastic leukemia. However, each individual may experience symptoms differently. The symptoms of acute lymphoblastic leukemia may resemble other blood disorders or medical problems. Always consult your doctor for a diagnosis.
Symptoms may include:
- Bleeding
- Bruising
- Fever
- Infections
- Persistent weakness
- Fatigue
- Loss of appetite
- Aches in bones and joints
- Swollen lymph nodes
- Weight loss
- Night sweats
- Swelling in the abdomen
- Trouble breathing
How Is Acute Lymphocytic Leukemia Diagnosed?
In addition to a complete medical history and physical examination, diagnostic procedures for acute lymphocytic leukemia may include the following:
- Blood tests
- Bone marrow aspiration and biopsy
- Cytogenetic analysis
- Immunophenotyping
- Lumbar puncture (spinal tap)
Additional blood tests and other evaluation procedures may also be performed.
How leukemia staging differs from that of other cancers
Most types of cancer are staged to communicate the size of the tumor and how far the cancer has spread. But leukemia rarely causes tumors. Because it is in your bone marrow and blood, it has already spread throughout your body. With ALL, doctors use different terms to describe the response of the leukemia to treatment.
Phases of ALL:
Untreated ALL
Your doctor has just diagnosed you with ALL. Your complete blood count (CBC) is abnormal. You have more than 5% immature white blood cells, called blasts, in your bone marrow. You probably have symptoms of leukemia, such as pain, fever, and bleeding. You have not been treated except to ease these symptoms.
ALL in Remission
You have received treatment for ALL. During this phase, your CBC is normal, you have less than 5% blasts, and you have no signs or symptoms of leukemia anywhere in your body.
Minimal Residual Disease
Your ALL appears to be in remission, but very sensitive lab tests are still able to detect leukemia cells in the bone marrow. Your ALL may be more likely to relapse, so you may benefit from further treatment to try to kill the remaining cells.
Refractory ALL
The leukemia has not gone away and is not responding to treatment.
Relapsed ALL (also called Recurrent ALL)
Your leukemia has returned after a period of remission. Your symptoms may return, your CBC becomes abnormal again, and you have at least 5% blasts. Because you will have already undergone treatment, your doctor may need to consider a new treatment plan to bring you back into remission.
