- Leukemia is a cancer of blood cells (and therefore sometimes referred to as blood cancer).
- While the exact causes of blood cancer is unknown, risk factors have been identified, including radiation exposure, certain chemotherapy for cancer, smoking, family history of leukemia, and exposure to certain chemicals such as benzene.
- Common symptoms of chronic or acute leukemia may include
- Leukemia type of cancers are grouped by how quickly the disease spreads (acute or chronic) as well as by the type of blood cell that is affected (lymphocytes or myelocytes). The four main types of leukemia include acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), acute myelocytic leukemia (AML), and chronic myelocytic leukemia (CML).
- People with leukemia are at significantly increased risk for developing infections, anemia, and bleeding. Other symptoms and signs include easy bruising, weight loss, night sweats, and unexplained fevers.
- The diagnosis of leukemia is supported by findings of the medical history and examination, and examining blood and bone marrow samples under a microscope.
- Treatment of leukemia depends on the type of leukemia, certain features of the leukemia cells, the extent of the disease, and prior history of treatment, as well as the age and health of the patient.
- Most patients with leukemia are treated with chemotherapy. Some patients also may have radiation therapy and/or bone marrow transplantation.
- There is no known way to prevent leukemia.
- The prognosis of leukemia depends upon several factors, including the patient’s age, the type of leukemia, and the extent to which the cancer has spread.
There are around 62,000 new cases of leukemia each year in the U.S. and about 24,500 deaths due to leukemia. Leukemia makes up about 3.7% of all new cancer cases.
Chronic leukemias develop slowly over time. These leukemias may not cause specific symptoms at the beginning of their course. If left untreated, the cells may eventually grow to high numbers, as in acute leukemias causing similar symptoms.
Exposure to radiation is known to increase the risk of developing AML, CML, or ALL. Increases in leukemia were observed in people surviving atomic bombs. Radiation therapy for cancer can also increase the risk of leukemia.
Most cases of leukemia are not believed to be hereditary, but certain genetic mutations and conditions can be passed along to offspring that increase the chances of developing leukemia. A condition known as Li-Fraumeni syndrome is characterized by an inherited mutation in a tumor suppressor gene known as TP53, and individuals with this condition have an increased risk of leukemia and other cancers. Other hereditary conditions that can increase the risk of developing leukemia include Down syndrome, neurofibromatosis type 1, ataxia telangiectasia, and Noonan syndrome.
Leukemia risk factors:
- Exposure to radiation is known to increase the risk of developing AML, CML, or ALL. Increases in leukemia were observed in people surviving atomic bombs. Radiation therapy for cancer can also increase the risk of leukemia. Exposure to certain chemicals, including benzene (used commonly in the chemical industry), increases the risk of leukemia. Cigarette smoking is known to increase the risk of developing AML.
- Certain genetic disorders can increase the risk; Down syndrome, Li-Fraumeni syndrome, and other medical conditions can increase the risk of developing leukemia. Blood disorders known as myelodysplastic syndromes confer an increased risk of developing AML. Human T-cell leukemia virus type 1 (HTLV-1) is a virus that causes a rare type of leukemia. Certain chemotherapy drugs for cancer can increase the risk for AML or ALL.
Having risk factors does not mean that a person will definitely get leukemia, and most people with risk factors will not develop the disease. Likewise, not everyone who develops leukemia has an identifiable risk factor.
American Society of Clinical Oncology. <http://www.cancer.net/>.
United States. National Cancer Institute. “Leukemia.” Sept. 2013. <http://www.cancer.gov/cancertopics/types/leukemia>.
United States. National Cancer Institute. “What you need to know about leukemia.” 2013. <http://www.cancer.gov/publications/patient-education/leukemia.pdf>.