Acute lymphocytic leukemia (ALL) is the most common cancer in childhood, although it can also occur in adults. ALL is a cancer of the blood and bone marrow. Cancer occurs when abnormal cells in a part of the body begin to grow out of control. ALL is caused by an increase in white blood cells called lymphocytes. Because ALL is an acute or aggressive form of cancer, it moves rapidly. ALL treatment should be given accordingly. Most types of ALL can be treated in children, and there is a good chance for a cure. However, ALL may also occur in adults, but the chances of cure are not as favorable for adults as they are for children.
According to statistics published by the American Cancer Society (ACS) about 6,050 new cases of ALL (3,450 males and 2,600 females) were diagnosed in the United States in 2012. Another 1,440 deaths (820 in males and 620 in females) from ALL were also reported. (ACS) Although most cases appeared in children, 4 out 5 deaths occurred in adults. Children younger than age 5 were at a higher risk of developing ALL. (ACS) However, children have been proven to do better because they can tolerate aggressive treatment much better than adults.
What Causes ALL? Are There Certain Risk Factors?
Although the true cause of ALL is not known, medical science have identified a few risk factors:
People who have been exposed to high levels of radiation, such as survivors of a nuclear reactor accident, have shown an increased risk for ALL. For example, the Japanese atomic bomb survivors of World War II had an increased risk of acute leukemia six to eight years after exposure. (Thompson, et al., 1994)
Studies done in the 1950s showed that a fetus exposed to radiation (like X-rays) within the first months of development presents an increased risk for ALL. However, more recent studies have failed to replicate these outcomes. (Journal of Family Practice) Nevertheless, it is still not recommended for pregnant women to undergo X-ray imaging.
Chemicals like hair dyes, benzene, and even chemotherapy drugs have shown a strong link to future development of ALL. (American Journal of Epidemiology)
Various viral infections have been linked to an increased risk for ALL. Infection with human T-cell lymphoma/leukemia virus-1 (HTLV-1) can cause a rare type of T-cell ALL, where T-cells are a particular type of white blood cell. Epstein-Barr Virus (EBV), which is usually responsible for infectious mononucleosis, has been linked to ALL and Burkitt’s lymphoma. (Ind. Jour. of Patho. & Micro.)
ALL does not appear to be an inherited disease, but some inherited syndromes exist with genetic changes that seem to raise the risk of ALL. These include Down syndrome, Klinefelter’s syndrome, Fanconi anemia, Bloom syndrome, ataxia-telangiectasia, and neurofibromatosis. People with siblings with ALL are also at an increased risk for the disease.
Although not well understood, African-Americans have shown higher risk for ALL than Caucasians. And men have a high tendency for ALL than women.
Other Risk Factors
Cigarette smoking, long exposure to diesel fuel, gasoline, pesticides, and electromagnetic fields have all been studied for possible links to ALL.
What Are The Symptoms of ALL?
Acute lymphocytic leukemia increases your chances of bleeding and developing infections. Symptoms that may arise include:
- paleness (pallor)
- bleeding from the gums
- fever due to infection (not the disease itself)
- bruises, purpura (bleeding within the skin), or petechiae (red or purple spots on the body)
- lymphadenopathy (enlarged lymph nodes can be felt in the neck, under the arms, or the groin region) and hepatosplenomegaly (enlargement of the liver or spleen)
- pain in the bones or joints
- weakness, fatigue, and shortness of breath
- testicular enlargement
- cranial nerve palsies
How Is ALL Diagnosed?
To diagnose ALL, a doctor must complete a full physical exam and conduct blood and bone marrows tests. He or she will likely ask about bone pain, as this is one of the first symptoms of ALL. Some of the possible diagnostic tests include:
Low hemoglobin and white blood cell count may or may not be increased. Low platelet count also can be found in patients suffering from ALL.
It may show immature cells circulating in the blood, which are normally found in bone marrow.
Bone Marrow Aspirate
Bone marrow aspiration (taking a sample of bone marrow from the pelvic or breast bone) provides a way to test for increased growth in marrow tissue, reduced production of red blood cells, and dysplasia (abnormal development of immature cells) in three cell lines in the presence of leukocytosis (increased white blood cells)
The widening of the mediastinum, or the “middle” partition of the chest, is often present.
CT (Computerized Tomography) Scan
This scan helps determine whether cancer has spread to the brain, spinal cord, or other parts of the body.
This is used to check the fluid in the spine to see if the cancer cells have spread to the spinal fluid.
The doctor may also conduct the following tests before deciding on a treatment plan.
Serum urea, renal, and liver biochemistry may be done.
Electrocardiogram and echocardiogram of the heart may be performed to check left ventricular function.
Treatment Options for ALL
Treatment of acute lymphocytic leukemia aims to bring the blood count back to normal. If this happens, and the bone marrow looks normal under microscopic examination, the cancer is said to be in remission.
Chemotherapy is used to treat this type of leukemia. For the first treatment, hospitalization for a few weeks may be required. Later, hospitalization for supervision should not be necessary and treatments can continue from the outpatient clinic.
In the event there is a low white blood cell count, an isolation room will likely be required to ensure protection from contagious diseases and other problems.
A bone marrow or stem cell transplant may be recommended if the leukemia does not respond to chemotherapy. The marrow to be transplanted may be taken from a brother or sister who is a complete match.
Since there is no confirmed cause for acute lymphocytic leukemia, the only known method of prevention is to avoid as many of the known risk factors as possible.