Entrectinib in children and young adults with solid or primary CNS tumors harboring NTRK, ROS1, or ALK aberrations (STARTRK-NG).

BACKGROUND: Entrectinib is a TRKA/B/C, ROS1, ALK tyrosine kinase inhibitor approved for the treatment of adults and children aged ≥12 years with NTRK fusion-positive solid tumors and adults with ROS1 fusion-positive non-small-cell lung cancer. We report an analysis of the STARTRK-NG trial, investigating the recommended phase 2 dose (RP2D) and activity of entrectinib in pediatric patients with solid tumors including primary central nervous system tumors. METHODS: STARTRK-NG (NCT02650401) is a phase 1/2 trial. Phase 1, dose-escalation of oral, once-daily entrectinib, enrolled patients aged <22 years with solid tumors with/without target NTRK1/2/3, ROS1, or ALK fusions. Phase 2, basket trial at the RP2D, enrolled patients with intracranial or extracranial solid tumors harboring target fusions or neuroblastoma. Primary endpoints: phase 1, RP2D based on toxicity; phase 2, objective response rate (ORR) in patients harboring target fusions. Safety-evaluable patients: ≥1 dose of entrectinib; response-evaluable patients: measurable/evaluable baseline disease and ≥1 dose at RP2D. RESULTS: At data cutoff, 43 patients, median age of 7 years, were response-evaluable. In phase 1, 4 patients experienced dose-limiting toxicities. The most common treatment-related adverse event was weight gain (48.8%). Nine patients experienced bone fractures (20.9%). In patients with fusion-positive tumors, ORR was 57.7% (95% CI 36.9-76.7), median duration of response was not reached, and median (interquartile range) duration of treatment was 10.6 months (4.2-18.4). CONCLUSIONS: Entrectinib resulted in rapid and durable responses in pediatric patients with solid tumors harboring NTRK1/2/3 or ROS1 fusions.

Genetic and histopathological associations with outcome in pediatric pilocytic astrocytoma.

OBJECTIVE: Pilocytic astrocytomas (PAs) have a generally favorable prognosis; however, progression or recurrence after resection is possible. The prognostic value of histopathological qualifiers (defined below) or BRAF alterations is not well understood. The aim of this study was to identify the prognostic value of genetic and histopathological features of pediatric PAs. METHODS: Patients treated for a WHO grade I PA at a single institution were analyzed for histopathological and genetic features and outcomes. "Histopathological qualifier" refers to designations such as "WHO grade I PA with increased proliferative index." BRAF alterations include gene fusions and point mutations. Patients with neurofibromatosis type 1 were excluded. RESULTS: A total of 222 patients were analyzed (51% female, mean age 9.6 years). Tumors were located in the cerebellum/fourth ventricle (51%), optic pathway/hypothalamus (15%), brainstem (12%), and cerebral cortex (11%). BRAF alterations were screened for in 77 patients and identified in 56 (73%). Histopathological qualifiers were present in 27 patients (14%). Resection was performed in 197 patients (89%), 41 (21%) of whom displayed tumor progression or recurrence after resection. Tumor progression or recurrence was not associated with histopathologic qualifiers (p = 0.36) or BRAF alterations (p = 0.77). Ki-67 proliferative indices were not predictive of progression or recurrence (p = 0.94). BRAF alterations, specifically KIAA1549 fusions, were associated with cerebellar/fourth ventricular tumor location (p < 0.0001) and younger patient age (p = 0.03). Patients in whom gross-total resection was achieved had lower rates of progression and recurrence (p < 0.0001). CONCLUSIONS: Histopathological features/qualifiers and BRAF alterations were not associated with tumor recurrence/progression in pediatric PAs. The extent of resection was the only factor analyzed that predicted outcome.

Multi-institutional analysis of treatment modalities in basal ganglia and thalamic germinoma.

BACKGROUND: Central nervous system (CNS) germinomas are treatment-sensitive tumors with excellent survival outcomes. Current treatment strategies combine chemotherapy with radiotherapy (RT) in order to reduce the field and dose of RT. Germinomas originating in the basal ganglia/thalamus (BGTGs) have proven challenging to treat given their rarity and poorly defined imaging characteristics. Craniospinal (CSI), whole brain (WBI), whole ventricle (WVI), and focal RT have all been utilized; however, the best treatment strategy remains unclear. METHODS: Retrospective multi-institutional analysis has been conducted across 18 institutions in four countries. RESULTS: For 43 cases of nonmetastatic BGTGs, the 5- and 10-year event-free survivals (EFS) were 85.8% and 81.0%, respectively, while the 5- and 10-year overall survivals (OS) were 100% and 95.5%, respectively (one patient fatality from unrelated cause). Median RT doses were as follows: CSI: 2250 cGy/cGy(RBE) (1980-2400); WBI: 2340 cGy/cGy(RBE) (1800-3000); WVI: 2340 cGy/cGy(RBE) (1800-2550); focal: 3600 cGy (3060-5400). Thirty-eight patients (90.5%) received chemotherapy. There was no statistically significant difference in the EFS based on initial field extent (p = .84). Nevertheless, no relapses were reported in patients who received CSI or WBI. Chemotherapy alone had significantly inferior EFS compared to combined therapy (p = .0092), but patients were salvageable with RT. CONCLUSION: Patients with BGTGs have excellent outcomes and RT proved to be an integral component of the treatment plan. This group of patients should be included in future prospective clinical trials and the best RT field should be investigated further.

Outcomes of BRAF V600E Pediatric Gliomas Treated With Targeted BRAF Inhibition.

PURPOSE: Children with pediatric gliomas harboring a BRAF V600E mutation have poor outcomes with current chemoradiotherapy strategies. Our aim was to study the role of targeted BRAF inhibition in these tumors. PATIENTS AND METHODS: We collected clinical, imaging, molecular, and outcome information from patients with BRAF V600E-mutated glioma treated with BRAF inhibition across 29 centers from multiple countries. RESULTS: Sixty-seven patients were treated with BRAF inhibition (pediatric low-grade gliomas [PLGGs], n = 56; pediatric high-grade gliomas [PHGGs], n = 11) for up to 5.6 years. Objective responses were observed in 80% of PLGGs, compared with 28% observed with conventional chemotherapy (P < .001). These responses were rapid (median, 4 months) and sustained in 86% of tumors up to 5 years while receiving therapy. After discontinuation of BRAF inhibition, 76.5% (13 of 17) of patients with PLGG experienced rapid progression (median, 2.3 months). However, upon rechallenge with BRAF inhibition, 90% achieved an objective response. Poor prognostic factors in conventional therapies, such as concomitant homozygous deletion of CDKN2A, were not associated with lack of response to BRAF inhibition. In contrast, only 36% of those with PHGG responded to BRAF inhibition, with all but one tumor progressing within 18 months. In PLGG, responses translated to 3-year progression-free survival of 49.6% (95% CI, 35.3% to 69.5%) versus 29.8% (95% CI, 20% to 44.4%) for BRAF inhibition versus chemotherapy, respectively (P = .02). CONCLUSION: Use of BRAF inhibition results in robust and durable responses in BRAF V600E-mutated PLGG. Prospective studies are required to determine long-term survival and functional outcomes with BRAF inhibitor therapy in childhood gliomas.

Mass cytometry detects H3.3K27M-specific vaccine responses in diffuse midline glioma.

BACKGROUNDPatients with diffuse midline gliomas (DMGs), including diffuse intrinsic pontine glioma (DIPG), have dismal outcomes. We previously described the H3.3K27M mutation as a shared neoantigen in HLA-A*02.01+, H3.3K27M+ DMGs. Within the Pacific Pediatric Neuro-Oncology Consortium, we assessed the safety and efficacy of an H3.3K27M-targeted peptide vaccine.METHODSNewly diagnosed patients, aged 3-21 years, with HLA-A*02.01+ and H3.3K27M+ status were enrolled in stratum A (DIPG) or stratum B (nonpontine DMG). Vaccine was administered in combination with polyinosinic-polycytidylic acid-poly-I-lysine carboxymethylcellulose (poly-ICLC) every 3 weeks for 8 cycles, followed by once every 6 weeks. Immunomonitoring and imaging were performed every 3 months. Imaging was centrally reviewed. Immunological responses were assessed in PBMCs using mass cytometry.RESULTSA total of 19 patients were enrolled in stratum A (median age,11 years) and 10 in stratum B (median age, 13 years). There were no grade-4 treatment-related adverse events (TRAEs). Injection site reaction was the most commonly reported TRAE. Overall survival (OS) at 12 months was 40% (95% CI, 22%-73%) for patients in stratum A and 39% (95% CI, 16%-93%) for patients in stratum B. The median OS was 16.1 months for patients who had an expansion of H3.3K27M-reactive CD8+ T cells compared with 9.8 months for their counterparts (P = 0.05). Patients with DIPG with below-median baseline levels of myeloid-derived suppressor cells had prolonged OS compared with their counterparts (P < 0.01). Immediate pretreatment dexamethasone administration was inversely associated with H3.3K27M-reactive CD8+ T cell responses.CONCLUSIONAdministration of the H3.3K27M-specific vaccine was well tolerated. Patients with H3.3K27M-specific CD8+ immunological responses demonstrated prolonged OS compared with nonresponders.TRIAL REGISTRATIONClinicalTrials.gov NCT02960230.FUNDINGThe V Foundation, the Pacific Pediatric Neuro-Oncology Consortium Foundation, the Pediatric Brain Tumor Foundation, the Mithil Prasad Foundation, the MCJ Amelior Foundation, the Anne and Jason Farber Foundation, Will Power Research Fund Inc., the Isabella Kerr Molina Foundation, the Parker Institute for Cancer Immunotherapy, and the National Institute of Neurological Disorders and Stroke (NINDS), NIH (R35NS105068).

Phase I study of vemurafenib in children with recurrent or progressive BRAFV600E mutant brain tumors: Pacific Pediatric Neuro-Oncology Consortium study (PNOC-002).

Background: BRAFV600E mutation is present in a subset of pediatric brain tumors. Vemurafenib is an oral, selective ATP-competitive inhibitor of BRAFV600E kinase. The goal of this multi-center study conducted through the Pacific Pediatric Neuro-Oncology Consortium (PNOC) was to determine the recommended phase 2 dose (RP2D) and dose limiting toxicities (DLTs) in children < 18 years with recurrent or progressive BRAFV600E mutant brain tumors. Results: Nineteen eligible patients were enrolled. Eleven patients had received three or more prior therapies. Data reported are from the start of treatment for the first patient (April 30 2014) through August 31 2019. The RP2D was defined as 550 mg/m2 twice daily after DLT criteria adjustment for rash. Related grade ≥ 3 adverse events included secondary keratoacanthoma (n = 1); rash (n =16); and fever (n = 5). Subjects received a median of 23 cycles (range 3-63). Four patients remain on treatment. Centrally reviewed best radiographic responses included 1 complete response, 5 partial responses, and 13 stable disease. The steady-state area under the curve (AUC0-∞median) was 604 mg*h/L (range 329-1052). Methods: Vemurafenib was given starting at 550 mg/m2, twice daily which corresponds to the adult RP2D. Adverse events were graded using the NIH Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Central imaging review was performed. Pharmacokinetic sampling was performed. Conclusions: Vemurafenib has promising anti-tumor activity in recurrent BRAF V600E-positive brain tumors with manageable toxicity. A phase 2 study is ongoing (NCT01748149).

Widely Metastatic Choroid Plexus Carcinoma Associated with Novel TP53 Somatic Mutation.

BACKGROUND: Choroid plexus carcinoma (CPC) is a rare, malignant tumor occurring more commonly in children than adults. This case report describes the clinical course of a 3-year-old boy with a rare case of metastatic CPC with a novel TP53 mutation. CASE DESCRIPTION: A 3-year-old boy presented with postconcussive symptoms after a fall. Computed tomography and magnetic resonance imaging revealed lesions in the suprasellar cistern, left lateral ventricle, and cauda equina. The tumor was diagnosed as choroid plexus carcinoma with a novel TP53 V216M somatic mutation. The patient underwent resection of the left lateral ventricle lesion. CONCLUSION: We describe a case of CPC with highly metastatic characteristics and a novel TP53 mutation. Our report implicates TP53 in the pathogenesis of pediatric CPC, and we emphasize that CPC in children should prompt careful consideration of TP53 status to inform prognosis and clinical treatment.

Prospective feasibility and safety assessment of surgical biopsy for patients with newly diagnosed diffuse intrinsic pontine glioma.

Background: Diagnosis of diffuse intrinsic pontine glioma (DIPG) has relied on imaging studies, since the appearance is pathognomonic, and surgical risk was felt to be high and unlikely to affect therapy. The DIPG Biology and Treatment Study (DIPG-BATS) reported here incorporated a surgical biopsy at presentation and stratified subjects to receive FDA-approved agents chosen on the basis of specific biologic targets. Methods: Subjects were eligible for the trial if the clinical features and imaging appearance of a newly diagnosed tumor were consistent with a DIPG. Surgical biopsies were performed after enrollment and prior to definitive treatment. All subjects were treated with conventional external beam radiotherapy with bevacizumab, and then stratified to receive bevacizumab with erlotinib or temozolomide, both agents, or neither agent, based on O6-methylguanine-DNA methyltransferase status and epidermal growth factor receptor expression. Whole-genome sequencing and RNA sequencing were performed but not used for treatment assignment. Results: Fifty-three patients were enrolled at 23 institutions, and 50 underwent biopsy. The median age was 6.4 years, with 24 male and 29 female subjects. Surgical biopsies were performed with a specified technique and no deaths were attributed to the procedure. Two subjects experienced grade 3 toxicities during the procedure (apnea, n = 1; hypertension, n = 1). One subject experienced a neurologic deficit (left hemiparesis) that did not fully recover. Of the 50 tumors biopsied, 46 provided sufficient tissue to perform the study assays (92%, two-stage exact binomial 90% CI: 83%-97%). Conclusions: Surgical biopsy of DIPGs is technically feasible, associated with acceptable risks, and can provide biologic data that can inform treatment decisions.

18F-FDOPA PET/MRI for monitoring early response to bevacizumab in children with recurrent brain tumors.

BACKGROUND: Noninvasively predicting early response to therapy in recurrent pediatric brain tumors provides a challenge. 3,4-dihydroxy-6-[18F]fluoro-L-phenylalanine (18F-FDOPA) PET/MRI has not been previously studied as a tool to evaluate early response to antiangiogenic therapy in children. The purpose of this study was to evaluate the safety and feasibility of using 18F-FDOPA PET/MRI to assess response to bevacizumab in children with relapsed brain tumors. MATERIALS AND METHODS: Six patients with recurrent gliomas (5 low-grade, 1 high-grade) planned to undergo treatment with bevacizumab were enrolled. 18F-FDOPA PET/MRI scans were obtained prior to and 4 weeks following the start of treatment, and these were compared with the clinical response determined at the 3-month MRI. The primary PET measure was metabolic tumor volume (MTV) at 10 to 15 min after 18F-FDOPA injection. For each tumor, the MTV was determined by manually defining initial tumor volumes of interest (VOI) and then applying a 1.5-fold threshold relative to the mean standardized uptake value (SUV) of a VOI in the frontal lobe contralateral to the tumor. RESULTS: 18F-FDOPA PET/MRI was well tolerated by all patients. All tumors were well visualized with 18F-FDOPA on the initial study, with peak tumor uptake occurring approximately 10 min after injection. Maximum and mean SUVs as well as tumor-to-brain ratios were not predictors of response at 3 months. Changes in MTVs after therapy ranged from 23% to 98% (n = 5). There is a trend towards the percent MTV change seen on the 4-week scan correlating with progression-free survival. CONCLUSION: 18F-FDOPA PET/MRI was well tolerated in pediatric patients and merits further investigation as an early predictor of response to therapy.

Large Vessel Arteriopathy After Cranial Radiation Therapy in Pediatric Brain Tumor Survivors.

Among childhood cancer survivors, increased stroke risk after cranial radiation therapy may be caused by radiation-induced arteriopathy, but limited data exist to support this hypothesis. Herein, we assess the timing and presence of cerebral arteriopathy identified by magnetic resonance angiography (MRA) after cranial radiation therapy in childhood brain tumor survivors. In a cohort of 115 pediatric brain tumor survivors, we performed chart abstraction and prospective annual follow-up to assess the presence of large vessel cerebral arteriopathy by MRA. We identified 10 patients with cerebral arteriopathy. The cumulative incidence of arteriopathy 5 years post-cranial radiation therapy was 5.4% (CI 0.6%-10%) and 10 years was 16% (CI 4.6%-26%). One patient had an arterial ischemic stroke 2.4 years post-cranial radiation therapy in the distribution of a radiation-induced stenotic artery. We conclude that large vessel arteriopathies can occur within a few years of cranial radiation therapy and can become apparent on MRA in under a year.

Unusual high-grade features in pediatric diffuse leptomeningeal glioneuronal tumor: comparison with a typical low-grade example.

Diffuse leptomeningeal glioneuronal tumor, a recent addition to the World Health Organization classification system, typically presents in the pediatric population with signs and symptoms related to elevated intracranial pressure and imaging characteristics that may mimic infectious etiologies. The tumor is usually low grade and tends to harbor BRAF rearrangement/duplication in up to 75% of cases, BRAF V600E mutation in a smaller subset of cases, and loss of chromosomal arm 1p in approximately 50%-60% of cases, with ~20% of those showing loss of both 1p and 19q (codeletion). We report here 2 contrasting cases of diffuse leptomeningeal glioneuronal tumors, one with typical low-grade features and an indolent, although not benign, course, in which the disease is currently successfully managed by chemotherapy, and a second case with unusually high-grade features on initial presentation, including frank anaplasia and elevated mitotic index, in which the disease showed an initial response to chemoradiation but ultimately was fatal.

Pilot Evaluation of a Palliative and End-of-Life Communication Intervention for Parents of Children With a Brain Tumor.

Providing timely palliative and end-of-life care (PC/EOL) information to parents of children with a serious illness is a national health care priority. The goals of this study were to determine feasibility, acceptability, and parent responses related to a PC/EOL communication intervention, titled "Communication Plan: Early through End of Life (COMPLETE)" to parents of children with a brain tumor. The study was a 2-site prospective, single-group pilot study targeting parents' stress and coping outcomes. The sample included 13 parents of 11 children (ie, 11 families). During the first 6 months postdiagnosis, we evaluated parent outcomes at 4 time points (baseline and 3 post-sessions). Our findings included significant decline in decision regret ( P = .0089); strong, significantly increased hope ( P ≤ .0001); and significantly decreased uncertainty ( P = .04). Over time, more than half of the parents (61.5%) preferred to receive information about their child's current condition and PC/EOL options. Our findings provide evidence to suggest that the COMPLETE intervention is feasible and acceptable and produces promising effects on 3 parent outcomes (ie, decision regret, hope, and uncertainty) in parents of children with a brain tumor. Further research is indicated to evaluate COMPLETE with a larger sample of parents of children with cancer and with a control group.

Presence of cerebral microbleeds is associated with worse executive function in pediatric brain tumor survivors.

BACKGROUND: A specific form of small-vessel vasculopathy-cerebral microbleeds (CMBs)-has been linked to various types of dementia in adults. We assessed the incidence of CMBs and their association with neurocognitive function in pediatric brain tumor survivors. METHODS: In a multi-institutional cohort of 149 pediatric brain tumor patients who received cranial radiation therapy (CRT) between 1987 and 2014 at age <21 years and 16 patients who did not receive CRT, we determined the presence of CMBs on brain MRIs. Neurocognitive function was assessed using a computerized testing program (CogState). We used survival analysis to determine cumulative incidence of CMBs and Poisson regression to examine risk factors for CMBs. Linear regression models were used to assess effect of CMBs on neurocognitive function. RESULTS: The cumulative incidence of CMBs was 48.8% (95% CI: 38.3-60.5) at 5 years. Children who had whole brain irradiation developed CMBs at a rate 4 times greater than those treated with focal irradiation (P < .001). In multivariable analysis, children with CMBs performed worse on the Groton Maze Learning test (GML) compared with those without CMBs (Z-score -1.9; 95% CI: -2.7, -1.1; P < .001), indicating worse executive function when CMBs are present. CMBs in the frontal lobe were associated with worse performance on the GML (Z-score -2.4; 95% CI: -2.9, -1.8; P < .001). Presence of CMBs in the temporal lobes affected verbal memory (Z-score -2.0; 95% CI: -3.3, -0.7; P = .005). CONCLUSION: CMBs are common and associated with neurocognitive dysfunction in pediatric brain tumor survivors treated with radiation.

Resolution of precocious puberty following resection of fourth ventricular medulloblastoma: case report.

Medulloblastoma is a malignant embryonal tumor that arises in the cerebellum and invades the fourth ventricle, often resulting in obstructive hydrocephalus. Patients typically present with symptoms related to increased intracranial pressure and cerebellar dysfunction. The authors report a rare case of classic medulloblastoma with central precocious puberty (CPP) as its only presenting symptom. A 7-year-old boy with no prior history of medulloblastoma presented with Tanner Stage IV testicular enlargement and a 4-month history of acne and pubic hair. Laboratory tests of blood samples demonstrated highly elevated luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone. Admission MRI of the brain revealed a mass in the posterior fossa, which bordered and compressed the fourth ventricle. The patient also exhibited mild lateral and third ventriculomegaly. Surgical options were discussed with the neurosurgical department. A suboccipital craniotomy and C-1 laminectomy were performed. A large mass was seen arising from the inferior surface of the vermis, and lying within the fourth ventricle. Gross-total microsurgical resection of the mass was performed. Histopathological investigation characterized the tumor as classic medulloblastoma. Follow-up laboratory tests of blood samples demonstrated a reduction of LH, FSH, and testosterone back to prepubertal levels. The patient then began radiation and chemotherapy. This report demonstrates that mild obstructive hydrocephalus due to a posterior fossa tumor may present with unexpected symptoms, such as CPP. To the authors' knowledge, precocious puberty has not yet been associated with medulloblastoma, although it has been found with other posterior fossa tumors. Extensive imaging of the CNS for patients presenting with CPP is recommended.

Grade II pilocytic astrocytoma in a 3-month-old patient with encephalocraniocutaneous lipomatosis (ECCL): case report and literature review of low grade gliomas in ECCL.

Encephalocraniocutaneous lipomatosis (ECCL) is a rare congenital syndrome with an unknown etiology. Since 1970, around 60 cases have been reported in English literature. ECCL is usually classified by cutaneous lesions and non-progressive intracranial or spinal lipomas; however three cases of ECCL associated with low grade glioma (LGG) have been described. We report on the fourth case of LGG in a patient with ECCL; a grade II pilocytic astrocytoma with pilomyxoid features in a 3-month-old male, the youngest in literature.

Evaluation of Physician and Nurse Dyad Training Procedures to Deliver a Palliative and End-of-Life Communication Intervention to Parents of Children with a Brain Tumor.

When a child's prognosis is poor, physicians and nurses (MDs/RNs) often struggle with initiating discussions about palliative and end-of-life care (PC/EOL) early in the course of illness trajectory. We describe evaluation of training procedures used to prepare MD/RN dyads to deliver an intervention entitled: Communication Plan: Early Through End of Life (COMPLETE) intervention. Our training was delivered to 5 pediatric neuro-oncologists and 8 pediatric nurses by a team of expert consultants (i.e., in medical ethics, communication, and PC/EOL) and parent advisors. Although half of the group received training in a 1-day program and half in a 2-day program, content for all participants included 4 modules: family assessment, goal-directed treatment planning, anticipatory guidance, and staff communication and follow-up. Evaluations included dichotomous ratings and qualitative comments on content, reflection, and skills practice for each module. Positive aspects of our training included parent advisers' insights, emphasis on hope and non-abandonment messages, written materials to facilitate PC/EOL communication, and an MD/RN dyad approach. Lessons learned and challenges related to our training procedures will be described. Overall, the MDs and RNs reported that our PC/EOL communication-training procedures were helpful and useful. Future investigators should carefully plan training procedures for PC/EOL communication interventions.

Outcomes of pediatric low-grade gliomas treated with radiation therapy: a single-institution study.

Radiation therapy is often considered the treatment of choice for low-grade gliomas. However, given the long-term effects of radiation on the developing brain, the appropriate use of radiation therapy in pediatric patients remains controversial. The purpose of this study was to evaluate progression-free survival (PFS) of pediatric low-grade glioma patients treated with radiation therapy. Data were obtained through a retrospective chart review of patients treated between 1991 and 2008 from a single tertiary care center in the midwest. The study population consisted of 17 patients, of whom 8 (47%) had tumor recurrence after radiation therapy. The median follow-up time was 8.2 years, with a range of 2.3 to 17.2 years. The median age at diagnosis was 5.4 years, and the median age at radiation therapy was 9.4 years. The 3- and the 10-year PFS were 69%± 11.7% and 46%± 13.3%, respectively. A significant difference in PFS was seen when comparing brainstem tumors with hypothalamic/optic pathway tumors (P=0.019). Differences in PFS based on the age at diagnosis, the extent of initial surgery, and indication for radiation therapy were not significant. A larger multicenter study is needed to better assess PFS in these patients.

Rapidly progressive primary leptomeningeal atypical teratoid/rhabdoid tumor: a report of 2 cases.

Atypical teratoid/rhabdoid tumor is a rare, highly malignant central nervous system tumor most commonly occurring in very young children. Atypical teratoid/rhabdoid tumor most often presents as an expanding mass with symptoms consistent with the location of the tumor and may present with metastatic leptomeningeal disease. The authors describe 2 cases of rapidly progressive, diffuse leptomeningeal atypical teratoid/rhabdoid tumor without a solid primary mass. These cases demonstrate a clinical picture that can easily be confused with a basilar meningitis, encephalomyelitis, or vasculitis.