DTI assessment of the brainstem white matter tracts in pediatric BSG before and after therapy: a report from the Pediatric Brain Tumor Consortium.

PURPOSE: To assess changes in apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values in brainstem gliomas (BSG) in children and to observe the temporal evolution of changes in the white matter tracts following therapy using diffusion tensor imaging (DTI) analysis. METHODS: Serial ADC and FA measurements were obtained in three patients with newly diagnosed BSG on two approved treatment protocols. Values were compared with a set of normative ADC, FA, and eigenvalues of age-matched children of the corticospinal, transverse pontine and medial lemniscal tracts. Fiber tracking of the tracts coursing through the brainstem was performed using standard diffusion tractography analysis. RESULTS: We found increased ADC values within tumor at baseline compared to age-matched controls, with subsequent drop following treatment and subsequent increase with recurrence. Correspondingly, FA values were reduced at presentation, but transiently recovered during the phase of tumor response to treatment, and finally decreased significantly during tumor progression. These changes were concordant with the tractography analysis of white matter tracts in the brainstem. Based on these results, we suggest that initial changes in ADC and FA values reflects tract infiltration by tumor, but not complete disruption, whereas tumor progression results in complete loss of anisotropy possibly due to tract disruption. CONCLUSION: Serial changes in ADC and FA values and tractography data in pediatric BSG suggest initial tumor infiltration, with transient improvement on treatment and subsequent loss of tract anisotropy during tumor progression. This technique may have potential use in assessing response to treatment regimens for pediatric BSG.

Feasibility study: the effect of therapeutic yoga on quality of life in children hospitalized with cancer.

PURPOSE: To describe the effect of therapeutic yoga on child and parental reports of quality of life in children hospitalized with oncological diagnoses. METHODS: Six children participated in 5 yoga sessions over 2 months. The PedsQL 4.0 was administered to each child and participating parent/caregivers at baseline and after completion of the yoga intervention. The Wilcoxon nonparametric rank test measured individual differences over time. RESULTS: Statistically significant differences (P < .05) were found in child perception of gross motor function. CONCLUSION: These feasibility study data suggest that therapeutic yoga positively affected child perception of gross motor function measured on the PedsQL 4.0. Further studies are needed, including a randomized control trial and with a larger number of participants, to clarify and confirm the effect of therapeutic yoga.

ERBB1 is amplified and overexpressed in high-grade diffusely infiltrative pediatric brain stem glioma.

PURPOSE: This study was conducted to investigate the incidence of ERBB1 amplification and overexpression in samples of diffusely infiltrative (WHO grades II-IV) pediatric brain stem glioma (BSG) and determine the relationship of these abnormalities to expression and mutation of TP53 and tumor grade. EXPERIMENTAL DESIGN: After central pathology review, the incidence of ERBB1 amplification and overexpression was determined in 28 samples (18 surgical biopsy and 10 postmortem specimens) of BSG using quantitative PCR and immunohistochemistry, respectively. Mutation and expression of TP53 were also determined in these same samples by direct sequence analysis of microdissected tumor material and immunohistochemistry, respectively. All experimental procedures were performed blind to tumor grade. RESULTS: Twelve, 9, and 7 tumors were classified as WHO grades II, III, and IV, respectively. A significant increase in ERBB1 expression was observed with increasing tumor grade (P < 0.001). Two grade IV tumors displayed intense membranous ERBB1 expression in 90% of tumor cells in association with high-level ERBB1 gene amplification. One grade III tumor also contained low-level amplification of ERBB1. Six tumors demonstrated TP53 nuclear immunoreactivity, and six contained a mutation in TP53. No correlation was observed between abnormalities in TP53 and either tumor grade or amplification and overexpression of ERBB1. CONCLUSIONS: These data suggest that ERBB1 signaling is important for the development of childhood BSG and is worthy of study as a therapeutic target in this disease. Our data also indicate that the genetics of childhood BSG are complex and include both grade-dependent amplification and overexpression of ERBB1 and grade-independent expression and mutation of TP53.

Induction chemotherapy and conformal radiation therapy for very young children with nonmetastatic medulloblastoma: Children's Oncology Group study P9934.

PURPOSE: P9934 was a prospective trial of systemic chemotherapy, second surgery, and conformal radiation therapy (CRT) limited to the posterior fossa and primary site for children between 8 months and 3 years old with nonmetastatic medulloblastoma. The study was open from June 2000 until June 2006. PATIENTS AND METHODS: After initial surgery, children received four cycles of induction chemotherapy, followed by age- and response-adjusted CRT to the posterior fossa (18 or 23.4 Gy) and tumor bed (cumulative 50.4 or 54 Gy) and maintenance chemotherapy. Neurodevelopmental outcomes were evaluated and event-free survival (EFS) results were directly compared with a previous study of multiagent chemotherapy without irradiation (Pediatric Oncology Group [POG] trial 9233). RESULTS: Seventy-four patients met eligibility requirements. The 4-year EFS and overall survival probabilities were 50% ± 6% and 69% ± 5.5%, respectively, which compared favorably to the results from POG 9233. Analysis showed that the desmoplastic/nodular subtype was a favorable factor in predicting survival. Our 4-year EFS rate was 58% ± 8% for patients with desmoplasia. Whereas seven of 10 patients who had disease progression before CRT had primary-site failure, 15 of 19 patients who progressed after CRT had distant-site failure. Neurodevelopmental assessments did not show a decline in cognitive or motor function after protocol-directed chemotherapy and CRT. CONCLUSION: The addition of CRT to postoperative chemotherapy in young children with nonmetastatic medulloblastoma increased event-free survival compared with the use of postoperative chemotherapy alone. Future studies will use histopathologic typing (desmoplastic/nodular versus nondesmoplastic/nodular) to stratify patients for therapy by risk of relapse.

MRI as a central component of clinical trials analysis in brainstem glioma: a report from the Pediatric Brain Tumor Consortium (PBTC).

We report MRI findings from 2 pediatric clinical trials of diffuse intrinsic brainstem glioma (BSG) incorporating concurrent radiation therapy (RT) with molecularly targeted agents (gefitinib and tipifarnib). We determined associations of MRI variables with progression-free survival and overall survival and investigated effects of treatment on these variables. MRI (including diffusion and perfusion) was done before treatment, every 8 weeks (first year), every 12 weeks (thereafter), and at the end of treatment or disease progression. Reduced tumor volume (P < .0001) and tumor diffusion values (P <.0001) were apparent on the first post-RT/drug studies. Decreases in tumor volume correlated with pre-RT volume (P < .0001) and pre-RT diffusion values (P < .0001); larger decreases were noted for tumors with higher volumes and diffusion values. Patients with larger pre-RT tumors had longer progression-free survival (P < .0001). Patients with ≥ 25% decrease in tumor volume and diffusion values after RT had longer progression-free survival (P = .028) and overall survival (P = .0009). Enhancement at baseline and over time was significantly associated with shorter survival. Tumor diffusion values with baseline enhancement were significantly lower than those without (P = .0002). RT of BSG is associated with decreased tumor volume and intralesional diffusion values; patients with ≥ 25% decrease in values post-RT had relatively longer survival intervals, apparently providing an early imaging-based surrogate for relative outcomes. Patients with larger tumors and greater decreases in tumor volume and diffusion values had longer survival intervals. Tumor enhancement was associated with shorter survival, lower tumor diffusion values (increased cellularity), and a smaller drop in diffusion values after RT (P = .006). These associations justify continued investigation in other large clinical trials of brainstem glioma patients.