When the blasts crowd out the healthy cells in the bone marrow, your child begins to experience symptoms, such as a fever, bone pain and anemia.?????????ALL accounts for about 20 to 25 percent of all childhood cancer.??? ALL is the most common type of childhood leukemia, accounting for about 75 to 80 percent of childhood leukemias.??? Treatment for acute lymphoblastic leukemia is a long-term proce