Long-term follow-up and infectious complications of therapy for acute lymphoblastic leukemia in children

Infection is a major complication of therapy for acute lymphoblastic leukem ia (ALL) in children. Recent advances in supportive care have contributed t o improvements in long-term survivorship following treatment for ALL. Of 22 0 children treated for ALL on Dana-Farber Cancer Institute (DFCI) Consortiu m Protocol 85-001, a retrospective study of all 72 children at the DFCI and Maine Children's Cancer Program was conducted to determine the incidence a nd impact of infection in pediatric patients not on hematopoietic growth fa ctor support. There were two deaths on therapy, both of which were associat ed with infection. Our results show that severe infection, requiring hospit alization is far more likely to occur during induction therapy. The risk fo r hospitalization decreased during therapy, after remission was achieved wi th fewer children hospitalized during the continuation phase of therapy tha n during the intensification phase. Fever and neutropenia was the most comm on reason for hospitalization and in less than 30% of instances an etiology was determined. At a median follow-up of 9 years, the event-free survival (EFS) of the 220 patients enrolled on Protocol 85-001 was 78%. The 9 years EFS by risk groups (standard, high and very high risk) was 89%, 75% and 58% , respectively (p = 0.0005). In conclusion, serious infectious complication s were more likely to occur during induction and intensification. Thus, str ategies to prevent infection should be targeted to induction and intensific ation phases of therapy for childhood ALL.