Acute Lymphocytic Leukemia - Treatment to Achieve Remission

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Drugs Used for High-Risk Children. A four- or five-drug regimen is used for many high-risk children. An example of a four-drug regimen would be vincristine, prednisone/dexamethasone, plus asparaginase, and an anthracycline (such as doxorubicin, daunorubicin, or epirubicin).

Drugs Used for Specific High-Risk Adults. Adult patients have a poorer outlook than children, and researchers are looking for more effective chemotherapy regimens. For example, cyclophosphamide-based regimens are used in adult patients with certain types of ALL. In a 2005 study, patients treated with an investigational regimen of cytabarine and high-dose mitoxantrone experienced a much higher rate of remission and survival than patients treated with the standard L-20 chemotherapy regimen of vincristine, prednisone, cyclophosphamide, and doxorubicin. Patients with the Philadelphia chromosome also benefited from the investigational treatment.

Preventing Central Nervous System Disease (CNS Prophylaxis)

CNS prophylaxis is critical for preventing disease that has spread to the brain, spine, and testes (called sanctuary disease sites). Although only 3% of children with ALL have evidence of leukemia in the central nervous system (CNS) at the time of diagnosis, leukemia will spread to this region in between 50 - 70% of children without preventive (prophylactic) treatment. The brain is one of the first sites for relapsing leukemia.

CNS prophylaxis is usually:

• Administered together with induction therapy before moving to consolidation, the next standard treatment phase, particularly if there are any leukemic cells detected in the spinal fluid.
• Given through intrathecal chemotherapy, in which a drug is injected directly into the spinal fluid. The drugs used are either methotrexate alone or a combination of methotrexate, hydrocortisone, and cytarabine. (Induction chemotherapy does not penetrate the blood-brain barrier sufficiently to destroy leukemic cells in the brain.)
• In some cases, methotrexate, with or without other drugs, is given as systemic (widespread) therapy at the same time as intrathecal chemotherapy. The addition of this treatment is effective in preventing relapse in the central nervous system and can substitute for radiation to the skull.