[Treatment of acute lymphoid leukemia in children]

Nowadays 95% of children with acute lymphoblastic leukemia (ALL) achieved complete remission within four to six weeks and 70% are completely cured. An important principle is that treatment should vary to prognosis and intensification of prognostic factors is of paramount importance. Leukemic patients with a good prognosis should be spared of toxic treatment. In contrast, intensive treatment should be the rule for patients with reduced probability of long term survival. In most of the protocols, induction is followed by consolidation and intensification. Duration of maintenance treatment is 18 to 24 months. Central nervous system prophylaxis associates intrathecal treatment and high dose methotrexate whereas skull irradiation must be limited to children who have high risk of meningeal relapse. Marrow relapses remain a very difficult problem. With a new induction treatment, a second remission can be achieved in 75 to 90% of patients. Bone marrow transplantation is the treatment of choice for relapses occurring on treatment. For CNS relapses skull irradiation is mandatory with a new intensive treatment in order to avoid bone marrow relapse. During treatment peculiar attention must be payed to the occurrence of bacterial infection. These infections are related to white blood cell aplasia, antibiotics must be started immediately and in some cases the use of growth factors is discussed. Immune deficiency during maintenance treatment increases the risk of viral infections. Most of the surviving children have a good quality of life without major impairment of physical, intellectual or psychological functions.