Vorinostat and isotretinoin with chemotherapy in young children with embryonal brain tumors: A report from the Pediatric Brain Tumor Consortium (PBTC-026).

BACKGROUND: Embryonal tumors of the CNS are the most common malignant tumors occurring in the first years of life. This study evaluated the feasibility and safety of incorporating novel non-cytotoxic therapy with vorinostat and isotretinoin to an intensive cytotoxic chemotherapy backbone. METHODS: PBTC-026 was a prospective multi-institutional clinical trial for children <48 months of age with newly diagnosed embryonal tumors of the CNS. Treatment included three 21-day cycles of induction therapy with vorinostat and isotretinoin, cisplatin, vincristine, cyclophosphamide, and etoposide; three 28-day cycles of consolidation therapy with carboplatin and thiotepa followed by stem cell rescue; and twelve 28-day cycles of maintenance therapy with vorinostat and isotretinoin. Patients with M0 medulloblastoma (MB) received focal radiation following consolidation therapy. Molecular classification was by DNA methylation array. RESULTS: Thirty-one patients with median age of 26 months (range 6-46) received treatment on study; 19 (61%) were male. Diagnosis was MB in 20 and supratentorial CNS embryonal tumor in 11. 24/31 patients completed induction therapy within a pre-specified feasibility window of 98 days. Five-year progression-free survival (PFS) and overall survival (OS) for all 31 patients were 55 ± 15 and 61 ± 13, respectively. Five-year PFS was 42 ± 13 for group 3 MB (n = 12); 80 ± 25 for SHH MB (n = 5); 33 ± 19 for embryonal tumor with multilayered rosettes (ETMR, n = 6). CONCLUSION: It was safe and feasible to incorporate vorinostat and isotretinoin into an intensive chemotherapy regimen. Further study to define efficacy in this high-risk group of patients is warranted.

Predictors of mortality and tumor recurrence in desmoplastic infantile ganglioglioma and astrocytoma-and individual participant data meta-analysis (IPDMA).

PURPOSE: Desmoplastic infantile astrocytoma (DIA) and desmoplastic infantile ganglioglioma (DIG) are classified together as grade I neuronal and mixed neuronal-glial tumor of the central nervous system by the World Health Organization (WHO). These tumors are rare and have not been well characterized in terms of clinical outcomes. We aimed to identify clinical predictors of mortality and tumor recurrence/progression by performing an individual patient data meta-analysis (IPDMA) of the literature. METHODS: A systematic literature review from 1970 to 2020 was performed, and individualized clinical data for patients diagnosed with DIA/DIG were extracted. Aggregated data were excluded from collection. Outcome measures of interest were mortality and tumor recurrence/progression, as well as time-to-event (TTE) for each of these. Participants without information on these outcome measures were excluded. Cox regression survival analyses were performed to determine predictors of mortality and tumor recurrence / progression. RESULTS: We identified 98 articles and extracted individual patient data from 188 patients. The cohort consisted of 58.9% males with a median age of 7 months. The majority (68.1%) were DIGs, while 24.5% were DIAs and 7.5% were non-specific desmoplastic infantile tumors; DIAs presented more commonly in deep locations (p = 0.001), with leptomeningeal metastasis (p = 0.001), and was associated with decreased probability of gross total resection (GTR; p = 0.001). Gender, age, and tumor pathology were not statistically significant predictors of either mortality or tumor recurrence/progression. On multivariate survival analysis, GTR was a predictor of survival (HR = 0.058; p = 0.007) while leptomeningeal metastasis at presentation was a predictor of mortality (HR = 3.27; p = 0.025). Deep tumor location (HR = 2.93; p = 0.001) and chemotherapy administration (HR = 2.02; p = 0.017) were associated with tumor recurrence/progression. CONCLUSION: Our IPDMA of DIA/DIG cases reported in the literature revealed that GTR was a predictor of survival while leptomeningeal metastasis at presentation was associated with mortality. Deep tumor location and chemotherapy were associated with tumor recurrence / progression.

Radiation dose reduction during intra-arterial chemotherapy for retinoblastoma: a retrospective analysis of 96 consecutive pediatric interventions using five distinct protocols.

BACKGROUND: Intra-arterial chemotherapy (IAC) represents a mainstay of retinoblastoma treatment in children. Patients with retinoblastoma are uniquely at risk for secondary malignancies and are sensitive to the ionizing effects of radiation. OBJECTIVE: To retrospectively review a single institution's experience with IAC for retinoblastoma and the effect of variable intra-procedural imaging techniques on radiation exposure. MATERIALS AND METHODS: Twenty-four consecutive patients, with a mean age of 30.8±16.3 months (range: 3.2-83.4 months), undergoing IAC for retinoblastoma between May 2014 and May 2020 (72 months) were included. No patients were excluded. The primary outcome was radiation exposure and secondary outcomes included technical success and procedural adverse events. Technical success was defined as catheterization of the ophthalmic or meningolacrimal artery and complete delivery of chemotherapy. Each procedure was retrospectively reviewed and categorized as one of five imaging protocol types. Protocol types were characterized by uniplanar versus multiplanar imaging and digital subtraction angiographic versus roadmap angiographic techniques. Radiation exposure, protocol utilization, the association of protocol and radiation exposure were assessed. RESULTS: During 96 consecutive interventions, 109 ocular treatments were performed. Thirteen of the 96 (15.5%) treatments were bilateral. Ocular technical success was 106 of 109 (97.2%). All three treatment failures were successfully repeated within a week. Mean fluoroscopy time was 6.4±6.2 min (range: 0.7-31.1 min). Mean air kerma was 36.2±52.2 mGy (range: 1.4-215.0 mGy). There were two major (1.8%) complications and four (3.7%) minor complications. Of the 96 procedures, 10 (10.4%), 9 (9.4%), 13 (13.5%), 28 (29.2%) and 36 (37.5%) were performed using protocol types A, B, C, D and E, respectively. For protocol type A, mean fluoroscopy time was 10.3±6.8 min (range: 3.0-25.4 min) and mean air kerma was 118.2±61.2 mGy (range: 24.5-167.3 mGy). For protocol type E, mean fluoroscopy time was 3.1±3.2 min (range: 0.7-15.1 min) and mean air kerma was 5.4±4.2 mGy (range: 1.4-19.5 mGy). Fluoroscopy time and air kerma decreased over time, corresponding to the reduced use of multiplanar imaging and digital subtraction angiography. In the first quartile (procedures 1-24), 8 (33.3%), 7 (29.2%), 2 (8.3%), 6 (25.0%) and 1 (4.2%) were performed using protocol types A, B, C, D and E, respectively. Mean fluoroscopy time was 10.5±8.2 min (range: 2.4-28.1 min) and mean air kerma was 84.2±71.6 mGy (range: 12.8-215.0 mGy). In the final quartile (procedures 73-96), 24 (100%) procedures were performed using protocol type E. Mean fluoroscopy time was 3.5±4.0 min (range: 0.7-15.1 min) and mean air kerma was 5.0±4.3 mGy (range: 1.4-18.0 mGy), representing 66.7% and 94.1% reductions from the first quartile, respectively. Technical success in the second half of the experience was 100%. CONCLUSION: Sequence elimination, consolidation from biplane imaging to lateral-only imaging, and replacing digital subtraction with roadmap angiography dramatically reduced radiation exposure during IAC for retinoblastoma without adversely affecting technical success or safety.

Children with DIPG and high-grade glioma treated with temozolomide, irinotecan, and bevacizumab: the Seattle Children's Hospital experience.

INTRODUCTION: Beyond focal radiation, there is no consensus standard therapy for pediatric high-grade glioma (pHGG) and outcomes remain dismal. We describe the largest molecularly-characterized cohort of children with pHGG treated with a 3-drug maintenance regimen of temozolomide, irinotecan, and bevacizumab (TIB) following radiation. METHODS: We retrospectively reviewed 36 pediatric patients treated with TIB at Seattle Children's Hospital from 2009 to 2018 and analyzed survival using the Kaplan-Meier method. Molecular profiling was performed by targeted DNA sequencing and toxicities, steroid use, and palliative care utilization were evaluated. RESULTS: Median age at diagnosis was 10.9 years (18 months-18 years). Genetic alterations were detected in 26 genes and aligned with recognized molecular subgroups including H3 K27M-mutant (12), H3F3A G34-mutant (2), IDH-mutant (4), and hypermutator profiles (4). Fifteen patients (42%) completed 12 planned cycles of maintenance. Side effects associated with chemotherapy delays or modifications included thrombocytopenia (28%) and nausea/vomiting (19%), with temozolomide dosing most frequently modified. Median event-free survival (EFS) and overall survival (OS) was 16.2 and 20.1 months, with shorter survival seen in DIPG (9.3 and 13.3 months, respectively). Survival at 1, 2, and 5 years was 80%, 10% and 0% for DIPG and 85%, 38%, and 16% for other pHGG. CONCLUSION: Our single-center experience demonstrates tolerability of this 3-drug regimen, with prolonged survival in DIPG compared to historical single-agent temozolomide. pHGG survival was comparable to analogous 3-drug regimens and superior to historical agents; however, cure was rare. Children with pHGG remain excellent candidates for the study of novel therapeutics combined with standard therapy.

Differential trajectories of neurocognitive functioning in females versus males following treatment for pediatric brain tumors.

BACKGROUND: Female and male trajectories of cerebellar and lobar brain structures are sexually dimorphic, making sex a potential candidate moderator of neurocognitive late effects from radiation treatment. We sought to evaluate longitudinal neurocognitive functioning in male versus female children treated for posterior fossa brain tumors. METHODS: Fifty-one female and 63 male survivors of posterior fossa tumors completed neuropsychological testing at 2 timepoints. We included patients treated with surgical resection, chemotherapy, and radiation therapy. Multilevel mixed modeling was used to predict IQ score as a function of patient sex following treatment (~2 or ~4 years post treatment). Effect sizes were used as a measure of clinical significance. RESULTS: Multilevel models resulted in a significant sex by time interaction (F = 6.69, P = 0.011). Females' cognitive scores were considerably higher compared with males at 4 years posttreatment. Females demonstrated an average improvement of 7.61 standard score IQ points compared with a decline of 2.97 points for males at 4 years follow-up. Effect sizes for female IQ compared with male IQ at 4 years posttreatment were between 0.8 and 0.9. CONCLUSION: Trajectories of neurocognitive functioning following posterior fossa tumor treatment differed between female and male children. Sexual dimorphism in radiation late effects may alter treatment decisions in children. Research into sex-specific neuroprotective mechanisms underlying neurocognitive development following pediatric brain tumor treatments is warranted.

Desmoplastic Infantile Ganglioglioma/Astrocytoma (DIG/DIA) Are Distinct Entities with Frequent BRAFV600 Mutations.

Desmoplastic infantile ganglioglioma (DIG) and desmoplastic infantile astrocytoma (DIA) are extremely rare tumors that typically arise in infancy; however, these entities have not been well characterized in terms of genetic alterations or clinical outcomes. Here, through a multi-institutional collaboration, the largest cohort of DIG/DIA to date is examined using advanced laboratory and data processing techniques. Targeted DNA exome sequencing and DNA methylation profiling were performed on tumor specimens obtained from different patients (n = 8) diagnosed histologically as DIG/DIGA. Two of these cases clustered with other tumor entities, and were excluded from analysis. The remaining 16 cases were confirmed to be DIG/DIA by histology and by DNA methylation profiling. Somatic BRAF gene mutations were discovered in 7 instances (43.8%); 4 were BRAFV600E mutations, and 3 were BRAFV600D mutations. Three instances of malignant transformation were found, and sequencing of the recurrence demonstrated a new TP53 mutation in one case, new ATRX deletion in one case, and in the third case, the original tumor harbored an EML4-ALK fusion, also present at recurrence. DIG/DIA are distinct pathologic entities that frequently harbor BRAFV600 mutations. Complete surgical resection is the ideal treatment, and overall prognosis is excellent. While, the small sample size and incomplete surgical records limit a definitive conclusion about the risk of tumor recurrence, the risk appears quite low. In rare cases with wild-type BRAF, malignant progression can be observed, frequently with the acquisition of other genetic alterations.Implications: DIG/DIA are a distinct molecular entity, with a subset frequently harboring either BRAF V600E or BRAF V600D mutations. Mol Cancer Res; 16(10); 1491-8. ©2018 AACR.

Tumor Talk and Child Well-Being: Perceptions of "Good" and "Bad" News Among Parents of Children With Advanced Cancer.

CONTEXT: Little is known about how parents of children with advanced cancer classify news they receive about their child's medical condition. OBJECTIVE: To develop concepts of "good news" and "bad news" in discussions of advanced childhood cancer from parent perspectives. METHODS: Parents of children with advanced cancer cared for at three children's hospitals were asked to share details of conversations in the preceding three months that contained "good news" or "bad news" related to their child's medical condition. We used mixed methods to evaluate parent responses to both open-ended and fixed-response items. RESULTS: Of 104 enrolled parents, 86 (83%) completed the survey. Six (7%) parents reported discussing neither good nor bad news, 18 (21%) reported only bad news, 15 (17%) reported only good news, and 46 (54%) reported both good and bad news (one missing response). Seventy-six parents (88%) answered free-response items. Descriptions of both good and bad news discussions consisted predominantly of "tumor talk" or cancer control. Additional treatment options featured prominently, particularly in discussions of bad news (42%). Child well-being, an important good news theme, encompassed treatment tolerance, symptom reduction, and quality of life. CONCLUSION: A majority of parents of children with advanced cancer report discussing both good and bad news in the preceding three months. Although news related primarily to cancer control, parents also describe good news discussions related to their child's well-being. Understanding how parents of children with advanced cancer classify and describe the news they receive may enhance efforts to promote family-centered communication.

Quality of Life in Children With Advanced Cancer: A Report From the PediQUEST Study.

CONTEXT: Modifiable factors of health-related quality of life (HRQOL) are poorly described among children with advanced cancer. Symptom distress may be an important factor for intervention. OBJECTIVES: We aimed to describe patient-reported HRQOL and its relationship to symptom distress. METHODS: Prospective, longitudinal data from the multicenter Pediatric Quality of Life and Symptoms Technology study included primarily patient-reported symptom distress and HRQOL, measured at most weekly with the Memorial Symptoms Assessment Scale and Pediatric Quality of Life inventory, respectively. Associations were evaluated using linear mixed-effects models adjusting for sex, age, cancer type, intervention arm, treatment intensity, and time since disease progression. RESULTS: Of 104 enrolled patients, 49% were female, 89% were white, and median age was 12.6 years. Nine hundred and twenty surveys were completed over nine months of follow-up (84% by patients). The median total Pediatric Quality of Life score was 74 (interquartile range 63-87) and was "poor/fair" (e.g., <70) 38% of the time. "Poor/fair" categories were highest in physical (53%) and school (48%) compared to emotional (24%) and social (16%) subscores. Thirteen of 24 symptoms were independently associated with reductions in overall or domain-specific HRQOL. Patients commonly reported distress from two or more symptoms, corresponding to larger HRQOL score reductions. Neither cancer type, time since progression, treatment intensity, sex, nor age was associated with HRQOL scores in multivariable models. Among 25 children completing surveys during the last 12 weeks of life, 11 distressing symptoms were associated with reductions in HRQOL. CONCLUSION: Symptom distress is strongly associated with HRQOL. Future research should determine whether alleviating distressing symptoms improves HRQOL in children with advanced cancer.

Survival After Relapse of Medulloblastoma.

Survival after recurrence of medulloblastoma has not been reported in an unselected cohort of patients in the contemporary era. We reviewed 55 patients diagnosed with medulloblastoma between 2000 and 2010, and treated at Seattle Children's Hospital to evaluate patterns of relapse treatment and survival. Fourteen of 47 patients (30%) over the age of 3 experienced recurrent or progressive medulloblastoma after standard therapy. The median time from diagnosis to recurrence was 18.0 months (range, 3.6 to 62.6 mo), and site of recurrence was metastatic in 86%. The median survival after relapse was 10.3 months (range, 1.3 to 80.5 mo); 3-year survival after relapse was 18%. There were trend associations between longer survival and having received additional chemotherapy (median survival 12.8 vs. 1.3 mo, P=0.16) and radiation therapy (15.4 vs. 5.9 mo, P=0.20). Isolated local relapse was significantly associated with shorter survival (1.3 vs. 12.8 mo, P=0.009). Recurrence of medulloblastoma is more likely to be metastatic than reported in previous eras. Within the limits of our small sample, our data suggest a potential survival benefit from retreatment with cytotoxic chemotherapy and radiation even in heavily pretreated patients. This report serves as a baseline against which to evaluate novel therapy combinations.

Pilot Study of Intensive Chemotherapy With Peripheral Hematopoietic Cell Support for Children Less Than 3 Years of Age With Malignant Brain Tumors, the CCG-99703 Phase I/II Study. A Report From the Children's Oncology Group.

BACKGROUND: The primary goals of the Children's Cancer Group 99703 study were to assess the feasibility and tolerability of-as well as the response rate to-a novel dose-intensive chemotherapy regimen. METHODS: Between March 1998 and October 2004, 92 eligible patients were enrolled. Following biopsy/resection, patients received three identical cycles of Induction chemotherapy (vincristine, cyclophosphamide, etoposide, and cisplatin) administered every 21-28 days. Patients without tumor progression then received three consolidation cycles of marrow-ablative chemotherapy (thiotepa and carboplatin) followed by autologous hematopoietic cell rescue. RESULTS: The maximum tolerated dose of thiotepa was 10 mg/kg/day × 2 days per cycle. The toxic mortality rate was zero during induction and 2.6% during consolidation. Centrally evaluated response rates to induction and consolidation in evaluable patients with residual tumor were 73.3% and 66.7%, respectively. Disease progression rates on induction and consolidation were 4%. Five-year event-free survival and overall survival were 43.9 ± 5.2% and 63.6 ± 5% respectively. Gross total resection versus less than gross total resection were the only significant outcome comparisons: 5-year maximum tolerated dose and overall survival of 54.4 ± 7% versus 28.9 ± 7% (P = 0.0065) and 75.9 ± 8% versus 48.7 ± 8% (P = 0.0034), respectively. The 5-year maximum tolerated dose for localized (M0) versus metastatic (M1+) medulloblastoma was 67.5 ± 9.5% versus 30 ± 14.5% (P = 0.007). The 5-year maximum tolerated dose and overall survival for desmoplastic medulloblastoma patients versus other medulloblastoma were 78.6 ± 11% versus 50.5 ± 12% (P = 0.038) and 85.7 ± 9.4% versus 60.6 ± 11.6% (P = 0.046), respectively. CONCLUSIONS: This phase I dose-escalation study of marrow-ablative thiotepa regimen determined a maximum tolerated dose that had acceptable toxicity. Overall survival data justify this strategy for current Children's Oncology Group studies.

Medical management of invasive fungal infections of the central nervous system in pediatric cancer patients.

Fungal infections of the central nervous system (CNS) are associated with high mortality rates in immunocompromised patients. Surgical intervention is a mainstay of therapy, but not always possible. We describe the use of medical therapy for the treatment of CNS fungal infections in four pediatric cancer patients. Definitive resection was not performed in any patient. All patients initially received combination antifungal therapy with good clinical response; long-term survival was documented in two patients able to transition to long-term azole therapy. Prolonged antifungal therapy is an important option for treating invasive CNS fungal infections when surgery is not feasible.

Differences in parent-provider concordance regarding prognosis and goals of care among children with advanced cancer.

PURPOSE: Concordance between parents of children with advanced cancer and health care providers has not been described. We aimed to describe parent-provider concordance regarding prognosis and goals of care, including differences by cancer type. PATIENTS AND METHODS: A total of 104 pediatric patients with recurrent or refractory cancer were enrolled at three large children's hospitals. On enrollment, their parents and providers were invited to complete a survey assessing perceived prognosis and goals of care. Patients' survival status was retrospectively abstracted from medical records. Concordance was assessed via discrepancies in perceived prognosis, statistics, and McNemar's test. Distribution of categorical variables and survival rates across cancer type were compared with Fisher's exact and log-rank tests, respectively. RESULTS: Data were available from 77 dyads (74% of enrolled). Parent-provider agreement regarding prognosis and goals of care was poor (kappa, 0.12 to 0.30). Parents were more likely to report cure was likely (P < .001). The frequency of perceived likelihood of cure and the goal of cure varied by cancer type for both parents and providers (P < .001 to .004). Relatively optimistic responses were more common among parents and providers of patients with hematologic malignancies, although there were no differences in survival. CONCLUSION: Parent-provider concordance regarding prognosis and goals in advanced pediatric cancer is generally poor. Perceptions of prognosis and goals of care vary by cancer type. Understanding these differences may inform parent-provider communication and decision making.

Recurrent somatic mutations in ACVR1 in pediatric midline high-grade astrocytoma.

Pediatric midline high-grade astrocytomas (mHGAs) are incurable with few treatment targets identified. Most tumors harbor mutations encoding p.Lys27Met in histone H3 variants. In 40 treatment-naive mHGAs, 39 analyzed by whole-exome sequencing, we find additional somatic mutations specific to tumor location. Gain-of-function mutations in ACVR1 occur in tumors of the pons in conjunction with histone H3.1 p.Lys27Met substitution, whereas FGFR1 mutations or fusions occur in thalamic tumors associated with histone H3.3 p.Lys27Met substitution. Hyperactivation of the bone morphogenetic protein (BMP)-ACVR1 developmental pathway in mHGAs harboring ACVR1 mutations led to increased levels of phosphorylated SMAD1, SMAD5 and SMAD8 and upregulation of BMP downstream early-response genes in tumor cells. Global DNA methylation profiles were significantly associated with the p.Lys27Met alteration, regardless of the mutant histone H3 variant and irrespective of tumor location, supporting the role of this substitution in driving the epigenetic phenotype. This work considerably expands the number of potential treatment targets and further justifies pretreatment biopsy in pediatric mHGA as a means to orient therapeutic efforts in this disease.

A molecular biology and phase II trial of lapatinib in children with refractory CNS malignancies: a pediatric brain tumor consortium study.

High expression of ERBB2 has been reported in medulloblastoma and ependymoma; EGFR is amplified and over-expressed in brainstem glioma suggesting these proteins as potential therapeutic targets. We conducted a molecular biology (MB) and phase II study to estimate inhibition of tumor ERBB signaling and sustained responses by lapatinib in children with recurrent CNS malignancies. In the MB study, patients with recurrent medulloblastoma, ependymoma, and high-grade glioma (HGG) undergoing resection were stratified and randomized to pre-resection treatment with lapatinib 900 mg/m² dose bid for 7-14 days or no treatment. Western blot analysis of ERBB expression and pathway activity in fresh tumor obtained at surgery estimated ERBB receptor signaling inhibition in vivo. Drug concentration was simultaneously assessed in tumor and plasma. In the phase II study, patients, stratified by histology, received lapatinib continuously, to assess sustained response. Eight patients, on the MB trial (four medulloblastomas, four ependymomas), received a median of two courses (range 1-6+). No intratumoral target inhibition by lapatinib was noted in any patient. Tumor-to-plasma ratios of lapatinib were 10-20 %. In the 34 patients (14 MB, 10 HGG, 10 ependymoma) in the phase II study, lapatinib was well-tolerated at 900 mg/m² dose bid. The median number of courses in the phase II trial was two (range 1-12). Seven patients (three medulloblastoma, four ependymoma) remained on therapy for at least four courses range (4-26). Lapatinib was well-tolerated in children with recurrent or CNS malignancies, but did not inhibit target in tumor and had little single agent activity.

Diffusion tensor imaging of the superior cerebellar peduncle identifies patients with posterior fossa syndrome.

INTRODUCTION: Posterior fossa tumors are the most common brain tumor of children. Aggressive resection correlates with long-term survival. A high incidence of posterior fossa syndrome (PFS), impairing the quality of life in many survivors, has been attributed to damage to bilateral dentate nucleus or to cerebellar output pathways. Using diffusion tensor imaging (DTI), we examined the involvement of the dentothalamic tracts, specifically the superior cerebellar peduncle (SCP), in patients with posterior fossa tumors and the association with PFS. METHODS: DTI studies were performed postoperatively in patients with midline (n = 12), lateral cerebellar tumors (n = 4), and controls. The location and visibility of the SCP were determined. The postoperative course was recorded, especially with regard to PFS, cranial nerve deficits, and oculomotor function. RESULTS: The SCP travels immediately adjacent to the lateral wall of the fourth ventricle and just medial to the middle cerebellar peduncle. Patients with midline tumors that still had observable SCP did not develop posterior fossa syndrome (N = 7). SCPs were absent, on either preoperative (N = 1, no postoperative study available) or postoperative studies (N = 4), in the five patients who developed PFS. Oculomotor deficits of tracking were observed in patients independent of PFS or SCP involvement. CONCLUSION: PFS can occur with bilateral injury to the outflow from dentate nuclei. In children with PFS, this may occur due to bilateral injury to the superior cerebellar peduncle. These tracts sit immediately adjacent to the wall of the ventricle and are highly vulnerable when an aggressive resection for these tumors is performed.

Gross total resection correlates with long-term survival in pediatric patients with glioblastoma.

OBJECTIVE: Glioblastoma is a rare central nervous system neoplasm in pediatric patients. Few studies focused exclusively on this disease in this population. Available literature suggests that this disease behaves differently between pediatric and adult patients. We set out to study patients younger than 18 years of age, carrying the diagnosis of glioblastoma not of the brainstem, their clinical characteristics and clinical factors associated with clinical outcome. METHODS: Thirty-seven pediatric patients with the diagnosis of glioblastoma not of the brainstem, who were treated in our institution from 1982-2011, were identified and studied retrospectively. RESULTS: All patients underwent surgical intervention. Seventeen patients (45.9%) had gross total resection (GTR). Thirteen patients (35.1%) had subtotal resection and seven (18.9%) had biopsy. After surgery, 35 patients received radiation therapy (94.6%) and 34 patients (91.9%) received chemotherapy (various agents depending on the institutional protocols established at the time of treatment and family choice). Median follow-up time was 17.5 months, ranging from 0.5-186 months. The median overall survival is 18.7 months (95% confidence interval 15.7-21.8 months). The survival rate at 1, 2, and 5 years is 63.9%, 44.5%, and 17.6%, respectively. The median overall survival for patients with GTR is 45.1 months (95% confidence interval 27.5-62.8 months), 8.7 or 11.5 months for patients with subtotal resection or biopsy, respectively. GTR was accomplished only in patients with superficially located tumors. CONCLUSIONS: GTR significantly associates with long-term survival in our population of pediatric patients with glioblastoma not of the brainstem.

Communicating and understanding the purpose of pediatric phase I cancer trials.

PURPOSE: Quality informed consent should provide a clear understanding of the purpose of the research. Given the ethical challenges of pediatric phase I cancer trials, it is important to investigate physician-parent communication during informed consent conferences (ICCs) and parental understanding of the purpose of these studies. METHODS: In the multisite Informed Consent in Pediatric Phase I Cancer Trials study, 85 ICCs for phase I research between June 2008 and May 2011 were directly observed, and 60 parents were subsequently interviewed. The scientific purpose was defined as composite understanding of drug safety, dose finding, and dose escalation. We determined the frequency with which physicians explained these and other phase I-related concepts during the ICC. Parent interviews were analyzed to determine understanding. RESULTS: The child was present at 83 of 85 ICCs. Only 32% of parents demonstrated substantial understanding of the scientific purpose of phase I cancer trials; 35% demonstrated little or no understanding. Parents of higher socioeconomic status and racial majority status were more likely to understand the scientific purpose. Factors associated with understanding included physician explanation of the goal of the applicable phase I protocol offered (explained in 85% of ICCs) and explanation of the dose cohorts (explained in 43% of ICCs). Physicians explained drug safety in 23% of ICCs, dose finding in 52% of ICCs, and dose escalation in 53% of ICCs. CONCLUSION: Many parents of children participating in phase I trials do not understand the purpose of these trials. Physician-parent communication about the purpose of phase I research is lacking during ICCs.

Epilepsy surgery after treatment of pediatric malignant brain tumors.

Epilepsy surgery is common in the face of benign brain tumors, but rarely for patients with a history of malignant brain tumors. Seizures are a common sequelae in survivors of malignant pediatric brain tumors. Medical management alone may not adequately treat epilepsy, including in this group. We report four cases of patients who previously underwent gross total resection, radiation therapy, and chemotherapy for successful treatment of malignant brain neoplasia, yet suffered from medically intractable seizures. All underwent surgery for treatment of epilepsy with extension of the original resection. Despite the aggressive primary treatment of the neoplasm, and the potential for diffuse cerebral insults, all benefited from focal surgical resection. Aggressive surgical management of intractable epilepsy can be considered in survivors of malignant brain tumors.

A phase II study of O6-benzylguanine and temozolomide in pediatric patients with recurrent or progressive high-grade gliomas and brainstem gliomas: a Pediatric Brain Tumor Consortium study.

To estimate the sustained (≥8 weeks) objective response rate in pediatric patients with recurrent or progressive high-grade gliomas (HGG, Stratum A) or brainstem gliomas (BSG, Stratum B) treated with the combination of O6-benzylguanine (O6BG) and temozolomide(®) (TMZ). Patients received O6BG 120 mg/m(2)/d IV followed by TMZ 75 mg/m(2)/d orally daily for 5 consecutive days of each 28-day course. The target objective response rate to consider the combination active was 17%. A two-stage design was employed. Forty-three patients were enrolled; 41 were evaluable for response, including 25 patients with HGG and 16 patients with BSG. The combination of O6BG and TMZ was tolerable, and the primary toxicities were myelosuppression and gastrointestinal symptoms. One sustained (≥8 weeks) partial response was observed in the HGG cohort; no sustained objective responses were observed in the BSG cohort. Long-term (≥6 courses) stable disease (SD) was observed in 4 patients in Stratum A and 1 patient in Stratum B. Of the 5 patients with objective response or long-term SD, 3 underwent central review with 2 reclassified as low-grade gliomas. The combination of O6BG and TMZ did not achieve the target response rate for activity in pediatric patients with recurrent or progressive HGG and BSG.

Genome-wide analyses identify recurrent amplifications of receptor tyrosine kinases and cell-cycle regulatory genes in diffuse intrinsic pontine glioma.

PURPOSE: Long-term survival for children with diffuse intrinsic pontine glioma (DIPG) is less than 10%, and new therapeutic targets are urgently required. We evaluated a large cohort of DIPGs to identify recurrent genomic abnormalities and gene expression signatures underlying DIPG. PATIENTS AND METHODS: Single-nucleotide polymorphism arrays were used to compare the frequencies of genomic copy number abnormalities in 43 DIPGs and eight low-grade brainstem gliomas with data from adult and pediatric (non-DIPG) glioblastomas, and expression profiles were evaluated using gene expression arrays for 27 DIPGs, six low-grade brainstem gliomas, and 66 nonbrainstem low-grade gliomas. RESULTS: Frequencies of specific large-scale and focal imbalances varied significantly between DIPGs and nonbrainstem pediatric glioblastomas. Focal amplifications of genes within the receptor tyrosine kinase-Ras-phosphoinositide 3-kinase signaling pathway were found in 47% of DIPGs, the most common of which involved PDGFRA and MET. Thirty percent of DIPGs contained focal amplifications of cell-cycle regulatory genes controlling retinoblastoma protein (RB) phosphorylation, and 21% had concurrent amplification of genes from both pathways. Some tumors showed heterogeneity in amplification patterns. DIPGs showed distinct gene expression signatures related to developmental processes compared with nonbrainstem pediatric high-grade gliomas, whereas expression signatures of low-grade brainstem and nonbrainstem gliomas were similar. CONCLUSION: DIPGs comprise a molecularly related but distinct subgroup of pediatric gliomas. Genomic studies suggest that targeted inhibition of receptor tyrosine kinases and RB regulatory proteins may be useful therapies for DIPG.