Acute lymphocytic leukemia (ALL) is the most common childhood cancer. Approximately 70 percent of children with ALL in the United States are treated on clinical trials conducted by the Children’s Oncology Group (COG). 

Until the early 1960s, childhood ALL was incurable. Since then clinical trials have shown steadily increased cure rates and survival for children with ALL. The most recent combined data from these trials (patients enrolled between 2006 and 2009), have shown a five-year survival rate of approximately 92 percent.

One trial for which enrollment has been recently completed evaluated different chemotherapy regimens in T-cell ALL, a high-risk subset of ALL. This trial included over 1,000 patients and has shown an almost 90 percent survival rate — an outcome previously unheard of in this subtype of leukemia.

Using existing chemotherapy drugs, Stephen P. Hunger, MD, and researchers at the Center for Childhood Cancer Research, in concert with COG, are refining existing chemotherapeutic regimens to improve outcomes and decrease side effects by comparing previous standard-of-care chemotherapeutic regimens with modified regimens. 

Modifications may include the addition of new or different drugs, eliminating drugs, creating specific new combinations of drugs, changing dosing schedules (i.e., more or less frequent dosing of a drug), or changing the dosing of drugs. As survival rates improve, results are translated into newer, improved standard-of-care chemotherapeutic regimens. 

More than 2,000 children per year have been and are being treated in these clinical trials, resulting in significant improvements in survival for children with ALL.