What is childhood leukemia?

Scientists are not sure what causes childhood leukemia, but new research suggests it may due to unknown environmental factors, such as pesticides and processed meats like hot dogs and some deli meats.

The two main types of childhood leukemia are acute lymphocytic leukemia (ALL), which is about three-fourths of the leukemia’s diagnosed each year, and almost 18% of children diagnosed this year will have a much rare form of leukemia called acute myeloid leukemia (AML). ALL is a malignancy of lymphoid cells, a type of white blood cell found primarily in blood, bone marrow, lymph nodes, spleen, liver and the thymus. AML is a malignancy of the granulocyte family of white blood cells, found mainly in blood and bone marrow. Chronic myeloid leukemia (CML) is considered an adult cancer and usually affects adults in their late 60’s and 70’s.   All three types of leukemia and their sub-types are considered blood cancers.

Although medical science has evolved significantly in last decade, the treatment of childhood leukemia is still a major issue and a ‘cure’ still eludes doctors.  Modern medicine doesn’t hold the cure for leukemia and medical treatments available these days provide differentiated results.  Survival rates depend on the promptitude of diagnosis, the type of treatment, and the patients’ responsiveness to specific cancer therapies and treatments.  Although current treatment for childhood leukemia doesn’t always equal long-term survivorship, the progression of the disease can be slowed down and its malignant effects can be contained with the help of excellent medical care, research and chemotherapy.  Thus, the life expectancy of patients with leukemia has risen considerably in the last three decades.

The treatment of childhood leukemia is focused towards achieving a complete remission with minimal side-effects.  Complete remission refers to the absence of leukemia traces at the cellular level.  Children who present no evidence of malignant cellular activity after completing the treatment for childhood leukemia (protocols typically last about 2 1/2-3 1/2 years) are considered to be in remission.  By contrast, a relapse of such cells indicate a recurrence of leukemia specific symptoms and physiological signs.

In the case of patients with acute lymphocytic leukemia (ALL), a remission that lasts for more than five years after treatment has ended are considered to be long-term survivors.  This five-year period is critical for children with leukemia as is can make the difference between relapse and complete recovery.

In the last few decades, the five-year survival period of all types of childhood leukemia has tripled.  While in the 1960’s the five-year survival rate was around 15%, currently it is around 75%.  This five-year survival rate is strongly influenced by the child’s age and the type of leukemia at diagnosis (otherwise known as ‘risk factors’).  Statistics indicate that the standard risk, five-year survival rate for childhood ALL is around 60%, while the five-year survival rate for adults with chronic lymphocytic leukemia (CML), a more common adult cancer, is higher.  By contrast, the prognosis of children diagnosed with acute myeloid leukemia (AML) is less favorable, with the five-year survival rate of around 15%.

In spite of the fact that in the United States, the mortality rate for childhood leukemia has significantly decreased, it is still the leading cause of death among children diagnosed with cancer under the age of 15.