What Is Acute Lymphoblastic Leukemia (ALL)?

Acute lymphoblastic leukemia (ALL) is a cancer of the blood in which too many lymphocytes, a type of white blood cell, are produced by the bone marrow and by organs of the lymph system. The term "acute" indicates that the disease progresses rapidly.

Normally, the lymphocytes fight infection. But, in ALL, the cells are immature and overabundant. They crowd out other blood cells and may collect in the blood, bone marrow, and lymph tissue.

Acute leukemia can grow quickly and requires treatment as soon as possible after it is found. Chromosome abnormalities (extra chromosomes and structural changes in the chromosome material) are present in the majority of patients.

ALL is the most common form of childhood leukemia, with most children between the ages of two and four when the cancer is found. Despite being a common childhood cancer, about one-third of ALL cases occur in adults. According to the American Cancer Society, about 6,020 ALL cases are expected in 2014. The average person has about a one in 750 chance of developing ALL. In adults, the highest risk of developing the disease begins about age 50 and increases thereafter. Factors thought to increase the risk of developing ALL include past exposure to certain types of chemotherapy or radiation. Learn about childhood ALL.

Clinical Trials

Cancer Center doctors are active in developing and testing new therapies for the treatment of ALL. For example, our researchers have been on the forefront of analyzing outcomes of bone marrow transplants, and investigating genetic profiles that can help doctors make better decisions about ALL treatment. When appropriate, patients are invited to participate in studies to investigate the newest treatments as well as large-scale clinical trials for more established treatments.

Before beginning treatment, ask your doctor about any clinical trials you should consider. Learn more about clinical trials for cancer patients.

Clinical trial eligibility flowcharts

Eligibility flowcharts map clinical trials to specific types of cancers to determine if a participant is eligible for the particular clinical trial. View all hematology eligibility flowcharts at the Stanford Cancer Institute.

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