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Background Carboplatin is often adaptively dosed based on glomerular filtration rate (GFR), usually estimated by nuclear medicine tests. At least five pediatric adaptive dosing formulas have been developed. In an effort to standardize dosing in Children's Oncology Group protocols, we explored methodologic variation in GFR estimation and adaptive-dosing formula performance. Procedure Nuclear medicine GFR data from published series of ≥100 children with cancer were compared. Data from patients for whom body surface area, weight, GFR, and tracer half-life were available were used to compare formulas. Results Differences in methods used to estimate GFR in children with cancer resulted in highly variable population results, with median GFRs ranging from 96 to 150 mL/min/1.73m2 . The choice of adaptive formula had a major impact on calculated dose. When targeting an area under the curve of 7.9 mg/mL • min, the median difference between the formula yielding the lowest and highest carboplatin dose for individual subjects was 289 (range 96-1 737) mg/m2 . Conclusions Wide variation in GFR obtained with nuclear-medicine-based tests in children with cancer primarily results from systematic methodologic errors. Formulas for calculating carboplatin dose produce additional and substantial variation that may place children with cancer at unnecessary risk for excessive toxicity or underdosing. These findings indicate a need for the development of a uniform, validated method for GFR determination in children that should be utilized in all centers. Currently, adaptive dosing of carboplatin based on GFR has serious limitations and in most clinical settings should arguably not be used in place of body-surface-area-based dosing.

Traditional administration of rituximab requires careful titration and may involve many hours to minimize the risk of reactions. The objective of this study was to evaluate the safety of rapid infusions of rituximab in a pilot group of children with hematologic, oncologic, and rheumatologic disorders, and to determine the incidence of rate-related infusion reactions. Twenty patients enrolled in the study. All patients tolerated the rapid infusion of rituximab and no patient had an infusion-related reaction. We conclude that rapid infusions of rituximab are well tolerated and safe in our pilot group of patients.

Drug shortages require clinical teams to decide how to allocate drugs in limited supply among their patients. Ethical frameworks are invaluable for promoting rational approaches to drug distribution, but gaps remain between ethical theory and clinical application. The goal of this work was to explore how decision modeling could supplement ethical frameworks to inform drug distribution from the perspective of a clinical team.We created a hypothetical pediatric oncology clinic with a limited supply of 50,000 mg of methotrexate (MTX) and 21 patients due for treatment on one of six regimens. We constructed a simple decision analytic model to compare the effectiveness of MTX in milligrams per life year saved for each regimen. The robustness of the model was tested under various conditions including alternative drug effectiveness and time horizons. Effects on outcomes and distribution by substituting alternative dosing were explored for each regimen.Prescribed therapy for this group of patients required 108,791 mg MTX. Two regimens for three patients required ≥20,000 mg/mIn this hypothetical drug shortage, no allocation scenario exists that does not result in a worse outcome for some patients. Evidence of drug efficacy affected the decisions to substitute alternative treatments. First-come-first-served allocation resulted in fewer patients receiving treatment than allocation based on efficiency.

Approximately 18% of the United States' gross domestic product is attributed to healthcare expenditures. Several studies have illustrated that shifting healthcare from the inpatient to the outpatient setting is more cost effective, in addition to improving patient satisfaction. Vincristine, dactinomycin, and cyclophosphamide (VAC) are used together to treat children with solid tumors. Our traditional treatment approach included a two day inpatient admission. The purpose of this project was to establish a process for the administration of VAC in the outpatient setting to improve satisfaction, and reduce costs.We aimed to benchmark practice standards with other institutions, revised our treatment approach to permit outpatient administration, and implemented the new protocol in a stepwise manner. We collected caregiver satisfaction metrics through the use of surveys. Costs of encounters were obtained from administrative data. Total costs and costs by service type were compared using descriptive and mean comparisons.Seven patients received a total of 31 cycles of VAC in the outpatient setting. The time to achieve an appropriate pre-chemotherapy specific gravity was reduced by a median of 120 min. In addition, time spent in the hospital setting was reduced by a mean of 27.2 hr. Adverse effects were minimal and all caregivers reported greater satisfaction with the outpatient regimen. Outpatient administration of VAC was $3,300 less on average compared to the inpatient administration.Outpatient VAC provides a safe alternative for administration that reduces healthcare costs, reduces healthcare utilization, and improves patient satisfaction.

To determine the MTD of Seneca Valley Virus (NTX-010) in children with relapsed/refractory solid tumors. Patients (≥ 3-≤ 21 years) with neuroblastoma, rhabdomyosarcoma, or rare tumors with neuroendocrine features were eligible.Part A (single dose of NTX-010) enrolled 13 patients at three dose levels (1 × 10(9) viral particles (vp)/kg [n = 6], 1 × 10(10) vp/kg [n = 3], 1 × 10(11) vp/kg [n = 4]). Diagnoses included neuroblastoma (n = 9), rhabdomyosarcoma (n = 2), carcinoid tumor (n = 1), and adrenocorticocarcinoma (n = 1). Part B added cyclophosphamide (CTX) (oral CTX (25 mg/m(2) /day) days 1-14 and IV CTX (750 mg/m(2) ) days 8 and 29) to two doses of NTX-010 (1 × 10(11) vp/kg, days 8 and 29). Nine patients enrolled to Part B. Diagnoses included neuroblastoma (n = 3), rhabdomyosarcoma (n = 1), Wilms tumor (n = 3), and adrenocorticocarcinoma (n = 2).Twelve patients on Part A were evaluable for toxicity. There was a single DLT (grade 3 pain) at dose level 1. Additional grade ≥ 3 related adverse events (AEs) included leukopenia (n = 1), neutropenia (n = 3), lymphopenia (n = 3), and tumor pain (n = 1). No DLTs occurred on part B. Other grade ≥ 3 related AEs on Part B included: Leukopenia (n = 3), nausea (n = 1), emesis (n = 1), anemia (n = 1), neutropenia (n = 4), platelets (n = 1), alanine aminotransferase (n = 1), and lymphopenia (n = 2). All patients cleared NTX-010 from blood and stool by 3 weeks with 17/18 patients developing neutralizing antibodies.NTX-010 is feasible and tolerable at the dose levels tested in pediatric patients with relapsed/refractory solid tumors either alone or in combination with cyclophosphamide. However, despite the addition of cyclophosphamide, neutralizing antibodies appeared to limit applicability.

Mercaptopurine (6-MP), a critical component of acute lymphoblastic leukemia (ALL) therapy, is metabolized to 6-thioguanine (6-TGN) which is responsible for its anti-leukemic effect, and to 6-methylmercaptopurine nucleotides (6-MMPN/6-MMP) which can be hepatotoxic. Some patients preferentially metabolize 6-MP to 6-MMPN which may increase the risk of liver injury, reduce serum levels of 6-TGN and potentially increase the risk of relapse. The addition of allopurinol to oral 6-MP has been shown to optimize metabolism towards 6-TGN in patients with inflammatory bowel disease (IBD); however, this use has not been reported in patients undergoing treatment for ALL.

Malignant melanoma is rare in pediatrics, and therapies for patients with disseminated disease have not been well studied. This report describes our experience with the use of high-dose interleukin 2 (aldesleukin, IL-2) in a 2-year-old child with metastatic melanoma and describes our approach for the administration of this agent to young patients.

Background Recent advances have led to the development of oral iron chelators, which have changed clinical practice. The objective of this study was to descriptively assess the use of one such agent, deferasirox, as standard of care treatment in a large pediatric hematology center. Procedure We retrospectively studied all patients at the Texas Children's Hematology Center who were previously or currently treated with deferasirox. We gathered data on demographics, clinical diagnoses, length of time on chronic transfusions, previous use of deferoxamine, adherence to therapy, and reasons for discontinuation. We also assessed changes in serum ferritin, liver function tests, and creatinine for those on deferasirox for a minimum of 12 months. Results Fifty-nine patients were studied. Eighty-one percent of patients treated with deferasirox had a diagnosis of sickle cell disease. The mean baseline ferritin level for our study population was 2,117 ng/ml (range 754–7,211). Fifty-three percent of patients had been previously treated with deferoxamine. Adherence to oral therapy was documented in 76% of patients. For those on deferasirox for a minimum of 12 months, serum ferritin decreased in 30% of patients (44% of compliant patients, 11% of poorly compliant patients). Changes in creatinine and liver function tests were mild and did not result in long-term discontinuation of deferasirox in any cases. Conclusions Outside of controlled clinical trials, deferasirox can be utilized safely as an oral iron chelator in children although adherence to therapy and the complex interaction of factors that contribute to iron overload still present challenges for clinicians. Pediatr Blood Cancer 2009;52:616–620. © 2009 Wiley-Liss, Inc.