Leukemia

There are four main types. MedlinePlus sorts them by the kind of blood cell affected and by how fast they grow. They are acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL) and chronic myeloid leukemia (CML). NCI also covers rarer types, such as hairy cell leukemia. The American Cancer Society expects these new U.S. cases in 2026, as reported by SEER: about 22,760 of CLL, 22,720 of AML, 9,650 of CML and 6,250 of ALL.

It differs widely by type and by age. As a group, children and teens do better than adults, and CLL has much higher survival than AML. The outlook section on this page gives five-year figures from U.S. cancer registry data (SEER). Group numbers cannot predict what will happen to one person.

It depends on the type. Most children with ALL now do well. NCI reports that between 1975 and 2020, five-year survival for US children younger than 15 with ALL rose from 60% to about 90%. The chronic types are usually controlled rather than cured. NCI says treatment for CLL that is getting worse will not cure most people. For CML, NCI calls a donor transplant the only consistently successful cure. But daily TKI pills work so well that a transplant is no longer a first treatment for adults. It is mainly considered when the pills do not work well enough, cause too many side effects, or the disease advances.

Common signs include feeling very tired, fever or night sweats, and bruising or bleeding easily. Some people lose weight or appetite, or notice tiny red dots under the skin (petechiae). Chronic leukemia may cause no symptoms at first, and NCI notes CLL may be found on a routine blood test. These signs have many other causes. Blood tests, and often bone marrow tests, are used to diagnose leukemia.

Leukemia starts when bone marrow cells develop changes in their genetic material (DNA). MedlinePlus says the cause of these changes is unknown. Some things raise the risk. For AML, NCI lists older age, smoking, past chemotherapy or radiation, and exposure to benzene. For childhood ALL, it lists some inherited conditions, such as Down syndrome, Fanconi anemia and Li-Fraumeni syndrome. Not every child with a risk factor gets ALL, and some children with none do.

No. Many people are treated with chemotherapy, targeted medicines or other drugs alone. A donor stem cell transplant is used for selected people, most often with acute leukemia. In Europe, AML and ALL together account for more than half of all donor transplants. For CML and CLL, U.S. guidelines point to a transplant consultation mainly when the disease resists the main medicines or turns more aggressive.