There are many kinds of leukemia. Leukemias are part of a bigger group of diseases, the blood cancers (hematological neoplasms). Untreated, leukemia may lead to death within weeks to months. Chronic leukemias can last for years.
Four major types [change]
For this reason, all of the different forms of leukemia are categorized into four major types:
- Acute lymphocytic leukemia (ALL) is the most common type of leukemia. It is common in young children but can also be seen in old people.
- Chronic lymphocytic leukemia (CLL) is usually seen in people over the age of 55. It almost never affects children.
- Acute myelogenous leukemia (AML) occurs more commonly in adults than in children.
- Chronic myelogenous leukemia (CML) occurs more commonly in adults.
Causes and risk factors [change]
The causes of leukemia are not known in detail. In general, all cancers have a breakdown in the normal way cell division is controlled. Most likely, the different kinds of leukemias have different causes. The known causes account for relatively few cases. Most of the causes are outside our control. Researchers believe the following may influence whether a person develops leukemia:
- Exposure to Ionizing radiation
- Exposure to certain chemicals, for example benzene.
- Certain viruses
- Treatment with certain drugs that influence how cells develop; e.g. treatment of a tumor; Chemotherapy
- Certain genetic factors.
Viruses that are suspected to cause leukemia include:
- "WHO Disease and injury country estimates". World Health Organization. 2009. http://www.who.int/healthinfo/global_burden_disease/estimates_country/en/index.html. Retrieved 2009-11-11.
- "SEER Stat Fact Sheets: Leukemia". National Cancer Institute. 2011. http://seer.cancer.gov/statfacts/html/leuks.html#incidence-mortality. ""Approximately 10.8% were diagnosed under age 20""
- Ross J.A. et al (2002). "Diet and risk of leukemia in the Iowa Women's Health Study". Cancer Epidemiol. Biomarkers Prev. 11 (8): 777–81. PMID 12163333. http://cebp.aacrjournals.org/content/11/8/777.long.