These inconsistencies preclude a definitive conclusion as to the effect of chemotherapy on antioxidant status in patients undergoing anticancer therapy. However, our review suggests that total antioxidant status (measured by total radical antioxidant parameter) declines during cancer treatment. Adequately powered trials or observational studies among patients with a specific cancer diagnosis receiving a specific treatment regimen are needed to address patients' and physicians' concerns regarding these associations.

The use of unconventional therapies is highly prevalent among children with cancer and is not associated with demographic or clinical factors or participation in clinical trials. The possibility that an unconventional treatment may interact with a protocol treatment underscores the need for more information about the use of such therapies among all patients.

Mutations of Fms-like tyrosine kinase-3 (FLT3) have been described in about 30% of patients with acute myeloid leukemia (AML) and are associated with a shorter disease-free and overall survival after initial therapy. We sought to examine whether the presence of these mutations in relapsed disease was also associated with a poor response to salvage chemotherapy by comparing the outcome of 34 patients with diploid cytogenetics and mutated FLT3 (internal tandem duplication mutation – ITD) to 69 patients with normal karyotype and wild type FLT3 (FLT3-WT) in first relapse. On univariate analysis, patients with mutated FLT3 were less likely to achieve a CR to first salvage compared to FLT3-WT patients (24% vs. 41%; p=0.09). Furthermore, survival was longer for the FLT3-WT patients achieving a second CR after salvage compared to FLT3-mutated patients (p=0.017). Overall, patients with mutated FLT3 had a shorter survival from the time of relapse compared to those with FLT3-WT (p<0.001). The adverse prognostic impact of FLT3 mutations appears to persist beyond the initial treatment.

A large percentage of children undergoing treatment for acute lymphoblastic leukemia have inadequate intakes of antioxidants and vitamin A. Lower intakes of antioxidants are associated with increases in the adverse side effects of chemotherapy.