Leukemia is a rare type of cancer that affects the blood and bone marrow. It is the most common form of childhood cancer, accounting for about one-third of all cases in children under the age of 15. However, it is relatively rare in adults, accounting for only about 4% of cancer cases in those over the age of 20.
Leukemia is divided into four main types, based on the type of white blood cell that is affected. Acute lymphoblastic leukemia (ALL) is the most common type, accounting for around 75% of all cases. Chronic lymphocytic leukemia (CLL) is the second most common type, accounting for around 15% of cases. Acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) are much less common, accounting for around 10% and 5% of cases respectively.
In general, leukemia is not a very common cancer. According to the American Cancer Society, the overall incidence of leukemia in the United States is around 24 cases per 100,000 people each year. This puts it among the less common types of cancer, although it still affects thousands of people each year.
The prognosis for leukemia depends on a number of factors, including the type of leukemia and how advanced it is. In general, the five-year survival rate for all types of leukemia combined is around 66%. For ALL, the five-year survival rate is around 85%, while for CLL it is around 75%. The five-year survival rate for AML and CML is much lower, at around 40% and 60% respectively.
Overall, leukemia is a rare type of cancer, but it still affects thousands of people each year. Treatment and survival rates vary depending on the type of leukemia, but in general, the five-year survival rate for all types of leukemia combined is around 66%.