The relationship between imaging features, therapeutic response, and overall survival in pediatric diffuse intrinsic pontine glioma.

We aimed to evaluate the relationship between imaging features, therapeutic responses (comparative cross-product and volumetric measurements), and overall survival (OS) in pediatric diffuse intrinsic pontine glioma (DIPG). A total of 134 patients (≤ 18 years) diagnosed with DIPG were included. Univariate and multivariate analyses were performed to evaluate correlations of clinical and imaging features and therapeutic responses with OS. The correlation between cross-product (CP) and volume thresholds in partial response (PR) was evaluated by linear regression. The log-rank test was used to compare OS patients with discordant therapeutic response classifications and those with concordant classifications. In univariate analysis, characteristics related to worse OS included lower Karnofsky, larger extrapontine extension, ring-enhancement, necrosis, non-PR, and increased ring enhancement post-radiotherapy. In the multivariate analysis, Karnofsky, necrosis, extrapontine extension, and therapeutic response can predict OS. A 25% CP reduction (PR) correlated with a 32% volume reduction (R2 = 0.888). Eight patients had discordant therapeutic response classifications according to CP (25%) and volume (32%). This eight patients' median survival time was 13.0 months, significantly higher than that in the non-PR group (8.9 months), in which responses were consistently classified as non-PR based on CP (25%) and volume (32%). We identified correlations between imaging features, therapeutic responses, and OS; this information is crucial for future clinical trials. Tumor volume may represent the DIPG growth pattern more accurately than CP measurement and can be used to evaluate therapeutic response.

Clinical characteristics and prognostic factors of adult brainstem gliomas: A retrospective analysis of histologically-proven 40 cases.

To illustrate the clinical characteristics and prognostic factors of adult patients pathologically confirmed with brainstem gliomas (BSGs). Clinical data of 40 adult patients pathologically diagnosed with BSGs admitted to Beijing Shijitan Hospital from 2009 to 2022 were recorded and retrospectively analyzed. The primary parameters included relevant symptoms, duration of symptoms, Karnofsky performance status (KPS), tumor location, type of surgical resection, diagnosis, treatment, and survival. Univariate and multivariate analyses were evaluated by Cox regression models. The gliomas were located in the midbrain of 9 patients, in the pons of 14 cases, in the medulla of 5 cases, in the midbrain and pons of 6 cases and invading the medulla and pons of 6 cases, respectively. The proportion of patients with low-grade BSGs was 42.5%. Relevant symptoms consisted of visual disturbance, facial paralysis, dizziness, extremity weakness, ataxia, paresthesia, headache, bucking, dysphagia, dysacousia, nausea, dysphasia, dysosmia, hypomnesia and nystagmus. 23 (57.5%) patients accepted stereotactic biopsy, 17 (42.5%) patients underwent surgical resection. 39 patients received radiotherapy and 34 cases were treated with temozolomide. The median overall survival (OS) of all patients was 26.2 months and 21.5 months for the median progression-free survival (PFS). Both duration of symptoms (P = .007) and tumor grading (P = .002) were the influencing factors for OS, and tumor grading was significantly associated with PFS (P = .001). Duration of symptoms for more than 2 months and low-grade are favorable prognostic factors for adult patients with BSGs.

Laminin-associated integrins mediate Diffuse Intrinsic Pontine Glioma infiltration and therapy response within a neural assembloid model.

Diffuse Intrinsic Pontine Glioma (DIPG) is a highly aggressive and fatal pediatric brain cancer. One pre-requisite for tumor cells to infiltrate is adhesion to extracellular matrix (ECM) components. However, it remains largely unknown which ECM proteins are critical in enabling DIPG adhesion and migration and which integrin receptors mediate these processes. Here, we identify laminin as a key ECM protein that supports robust DIPG cell adhesion and migration. To study DIPG infiltration, we developed a DIPG-neural assembloid model, which is composed of a DIPG spheroid fused to a human induced pluripotent stem cell-derived neural organoid. Using this assembloid model, we demonstrate that knockdown of laminin-associated integrins significantly impedes DIPG infiltration. Moreover, laminin-associated integrin knockdown improves DIPG response to radiation and HDAC inhibitor treatment within the DIPG-neural assembloids. These findings reveal the critical role of laminin-associated integrins in mediating DIPG progression and drug response. The results also provide evidence that disrupting integrin receptors may offer a novel therapeutic strategy to enhance DIPG treatment outcomes. Finally, these results establish DIPG-neural assembloid models as a powerful tool to study DIPG disease progression and enable drug discovery.

Contemporary Management of Pediatric Brainstem Tumors.

Brain tumors are the second most common malignancy in childhood. Around 15-20% of pediatric brain tumors occur in the brainstem. The most common type of brainstem tumor are diffuse tumors in the ventral pons, whereas focal tumors tend to arise from the midbrain, medulla, and dorsal pons. Glioma is the most common pathological entity. Contemporary management consists of surgery, radiotherapy, chemotherapy, and other adjuvant treatment. Surgical options range from biopsy to radical excision. Biopsy can be performed for diagnostic and prognostic purposes, or in the setting of clinical trials, mainly for diffuse intrinsic pontine gliomas. For focal tumors, surgeons need to carefully balance clinical outcomes against possible neurological sequelae in order to achieve maximal safe resection. Radiotherapy is essential for control of high-grade tumors and may be applied to residual or recurrent low-grade tumors. Proton therapy may provide similar efficacy and less neurotoxicity in comparison to conventional photon therapy. Oncological treatment continues to evolve from conventional chemotherapy to targeted therapy, immunotherapy, and other novel treatment methods and holds great potential as adjuvant therapy for pediatric brainstem tumors.

Very Long-term Survivorship in Pediatric DIPG: Case Report and Review of the Literature.

Diffuse intrinsic pontine gliomas are lethal tumors with a prognosis generally less than 1 year. Few cases of survivors of 5 years or more have been reported. This case report highlights the journey of a 9.5-year survivor who underwent 3 rounds of focal radiotherapy; she experienced 6 years of progression-free survival following the first round but ultimately succumbed to her disease. An autopsy revealed a favorable IDH1 mutation and the absence of H3K27M. This case reiterates the importance of extensive molecular analyses in diffuse intrinsic pontine gliomas and explores the potential benefit of re-irradiation in patients with positive responses and long periods of remission.

Diffuse intrinsic pontine glioma (DIPG): A review of current and emerging treatment strategies.

Diffuse intrinsic pontine glioma (DIPG) is a childhood malignancy of the brainstem with a dismal prognosis. Despite recent advances in its understanding at the molecular level, the prognosis of DIPG has remained unchanged. This article aims to review the current understanding of the genetic pathophysiology of DIPG and to highlight promising therapeutic targets. Various DIPG treatment strategies have been investigated in pre-clinical studies, several of which have shown promise and have been subsequently translated into ongoing clinical trials. Ultimately, a multifaceted therapeutic approach that targets cell-intrinsic alterations, the micro-environment, and augments the immune system will likely be necessary to eradicate DIPG.

[Primary tumors of the brain stem. State of the problem]. / Pervichnye opukholi stvola golovnogo mozga. Sostoyanie problemy.

Primary brainstem gliomas are still poorly studied in neurooncology. This concept includes tumors with different histological and genetic features, as well as variable clinical course and outcomes. Nevertheless, treatment implies radiotherapy without a clear idea of morphological substrate of disease in 80% of cases. Small number of studies and insufficient data on histological and genetic nature of brainstem tumors complicate clear diagnostic and treatment algorithms. This review provides current information regarding primary glial brainstem tumors. Appropriate problems and objectives are highlighted. The purpose of the review is to provide a comprehensive and updated understanding of the current state of brainstem glial tumors and to identify areas requiring further study for improvement of diagnosis and treatment of these diseases. Brainstem tumors are an understudied problem with small amount of data that complicates optimal treatment strategies. Further researches and histological verification are required to develop new methods of therapy, especially for diffuse forms of neoplasms.

Decoding the puzzle: A multidisciplinary systematic review of adult brainstem glioma.

Adult brainstem gliomas (BSGs) are a group of rare central nervous system tumors with varying prognoses and controversial standard treatment strategies. To provide an overview of current trends, a systematic review using the PRISMA guidelines, Class of evidence (CE) and strength of recommendation (SR), was conducted. The review identified 27 studies. Surgery was found to have a positive impact on survival, particularly for focal lesions with CE II SR C. Stereotactic image-guided biopsy was recommended when resective surgery was not feasible with CE II and SR B. The role of systemic treatments remains unclear. Eight studies provided molecular biology data. This review gathers crucial literature on diagnosis and management of adult BSGs. It provides evidence-based guidance with updated recommendations for diagnosing and treating, taking into account recent molecular and genetic advancements. The importance of brain biopsy is emphasized to optimize treatment using emerging genetic-molecular findings and explore potential targeted therapies.

Experience in treating children with ocular dyskinesia and hemifacial spasm secondary to pontine tumours adjacent to the fourth ventricle and systematic review.

OBJECTIVE: To investigate the treatment plan and prognosis of children with ocular dyskinesia and hemifacial spasm secondary to pontine tumours adjacent to the fourth ventricle. METHODS: In this retrospective study, the clinical information of 10 consecutively collected children with ocular dyskinesia and hemifacial spasm secondary to pontine tumours adjacent to the fourth ventricle was analyzed. All 10 children underwent pontine tumour resection through a trans-cerebellomedullary fissure approach; 4 children underwent preoperative diffusion tensor imaging scans to determine the relationship between the tumour and facial nerve nucleus, and the other 6 children underwent intraoperative deep electroencephalography (EEG) tumour monitoring, in which the tumour electrical discharge activity of the tumour was recorded. A voxel distribution map was established to describe the distribution of the tumour location, and patient prognosis was evaluated through clinical and imaging follow-up. RESULTS: All 10 children achieved total tumour resection; 9 tumours were pathologically suggested to be ganglioglioma (WHO grade I), and 1 was a hamartoma. The symptoms of the original ocular dyskinesia and hemifacial spasm disappeared immediately after the operation. The children were followed up for 4-75 months, and none of the symptoms recurred; four cases with preoperative diffusion tensor imaging showed that the tumour was close to the facial nerve. Four in six intraoperative electrophysiological monitoring showed that the tumour had electrical discharge behaviour, and the tumour distribution map indicates a high density of tumour presence in the facial nerve nucleus and the nucleus of the abducens nerve. CONCLUSIONS: In paediatric patients, the facial symptoms are related to the location and abnormal electrical discharge of the tumour. There is no significant correlation between ocular dyskinesia and the location of the tumour. Conventional antiepileptic therapy for this disease is ineffective, and early surgical intervention for total tumour resection can achieve a clinical curative effect.

Fimepinostat Impairs NF-κB and PI3K/AKT Signaling and Enhances Gemcitabine Efficacy in H3.3K27M-Diffuse Intrinsic Pontine Glioma.

Diffuse intrinsic pontine glioma (DIPG) is the most aggressive pediatric brain tumor, and the oncohistone H3.3K27M mutation is associated with significantly worse clinical outcomes. Despite extensive research efforts, effective approaches for treating DIPG are lacking. Through drug screening, we identified the combination of gemcitabine and fimepinostat as a potent therapeutic intervention for H3.3K27M DIPG. H3.3K27M facilitated gemcitabine-induced apoptosis in DIPG, and gemcitabine stabilized and activated p53, including increasing chromatin accessibility for p53 at apoptosis-related loci. Gemcitabine simultaneously induced a prosurvival program in DIPG through activation of RELB-mediated NF-κB signaling. Specifically, gemcitabine induced the transcription of long terminal repeat elements, activated cGAS-STING signaling, and stimulated noncanonical NF-κB signaling. A drug screen in gemcitabine-treated DIPG cells revealed that fimepinostat, a dual inhibitor of HDAC and PI3K, effectively suppressed the gemcitabine-induced NF-κB signaling in addition to blocking PI3K/AKT activation. Combination therapy comprising gemcitabine and fimepinostat elicited synergistic antitumor effects in vitro and in orthotopic H3.3K27M DIPG xenograft models. Collectively, p53 activation using gemcitabine and suppression of RELB-mediated NF-κB activation and PI3K/AKT signaling using fimepinostat is a potential therapeutic strategy for treating H3.3K27M DIPG. SIGNIFICANCE: Gemcitabine activates p53 and induces apoptosis to elicit antitumor effects in H3.3K27M DIPG, which can be enhanced by blocking NF-κB and PI3K/AKT signaling with fimepinostat, providing a synergistic combination therapy for DIPG.

Targeting DNA Repair and Survival Signaling in Diffuse Intrinsic Pontine Gliomas to Prevent Tumor Recurrence.

Therapeutic resistance remains a major obstacle to successful clinical management of diffuse intrinsic pontine glioma (DIPG), a high-grade pediatric tumor of the brain stem. In nearly all patients, available therapies fail to prevent progression. Innovative combinatorial therapies that penetrate the blood-brain barrier and lead to long-term control of tumor growth are desperately needed. We identified mechanisms of resistance to radiotherapy, the standard of care for DIPG. On the basis of these findings, we rationally designed a brain-penetrant small molecule, MTX-241F, that is a highly selective inhibitor of EGFR and PI3 kinase family members, including the DNA repair protein DNA-PK. Preliminary studies demonstrated that micromolar levels of this inhibitor can be achieved in murine brain tissue and that MTX-241F exhibits promising single-agent efficacy and radiosensitizing activity in patient-derived DIPG neurospheres. Its physiochemical properties include high exposure in the brain, indicating excellent brain penetrance. Because radiotherapy results in double-strand breaks that are repaired by homologous recombination (HR) and non-homologous DNA end joining (NHEJ), we have tested the combination of MTX-241F with an inhibitor of Ataxia Telangiectasia Mutated to achieve blockade of HR and NHEJ, respectively, with or without radiotherapy. When HR blockers were combined with MTX-241F and radiotherapy, synthetic lethality was observed, providing impetus to explore this combination in clinically relevant models of DIPG. Our data provide proof-of-concept evidence to support advanced development of MTX-241F for the treatment of DIPG. Future studies will be designed to inform rapid clinical translation to ultimately impact patients diagnosed with this devastating disease.

Indoximod-based chemo-immunotherapy for pediatric brain tumors: A first-in-children phase I trial.

BACKGROUND: Recurrent brain tumors are the leading cause of cancer death in children. Indoleamine 2,3-dioxygenase (IDO) is a targetable metabolic checkpoint that, in preclinical models, inhibits anti-tumor immunity following chemotherapy. METHODS: We conducted a phase I trial (NCT02502708) of the oral IDO-pathway inhibitor indoximod in children with recurrent brain tumors or newly diagnosed diffuse intrinsic pontine glioma (DIPG). Separate dose-finding arms were performed for indoximod in combination with oral temozolomide (200 mg/m2/day x 5 days in 28-day cycles), or with palliative conformal radiation. Blood samples were collected at baseline and monthly for single-cell RNA-sequencing with paired single-cell T cell receptor sequencing. RESULTS: Eighty-one patients were treated with indoximod-based combination therapy. Median follow-up was 52 months (range 39-77 months). Maximum tolerated dose was not reached, and the pediatric dose of indoximod was determined as 19.2 mg/kg/dose, twice daily. Median overall survival was 13.3 months (n = 68, range 0.2-62.7) for all patients with recurrent disease and 14.4 months (n = 13, range 4.7-29.7) for DIPG. The subset of n = 26 patients who showed evidence of objective response (even a partial or mixed response) had over 3-fold longer median OS (25.2 months, range 5.4-61.9, p = 0.006) compared to n = 37 nonresponders (7.3 months, range 0.2-62.7). Four patients remain free of active disease longer than 36 months. Single-cell sequencing confirmed emergence of new circulating CD8 T cell clonotypes with late effector phenotype. CONCLUSIONS: Indoximod was well tolerated and could be safely combined with chemotherapy and radiation. Encouraging preliminary evidence of efficacy supports advancing to Phase II/III trials for pediatric brain tumors.

Chaetocin-mediated SUV39H1 inhibition targets stemness and oncogenic networks of diffuse midline gliomas and synergizes with ONC201.

BACKGROUND: Diffuse intrinsic pontine gliomas (DIPG/DMG) are devastating pediatric brain tumors with extraordinarily limited treatment options and uniformly fatal prognosis. Histone H3K27M mutation is a common recurrent alteration in DIPG and disrupts epigenetic regulation. We hypothesize that genome-wide H3K27M-induced epigenetic dysregulation makes tumors vulnerable to epigenetic targeting. METHODS: We performed a screen of compounds targeting epigenetic enzymes to identify potential inhibitors for the growth of patient-derived DIPG cells. We further carried out transcriptomic and genomic landscape profiling including RNA-seq and CUT&RUN-seq as well as shRNA-mediated knockdown to assess the effects of chaetocin and SUV39H1, a target of chaetocin, on DIPG growth. RESULTS: High-throughput small-molecule screening identified an epigenetic compound chaetocin as a potent blocker of DIPG cell growth. Chaetocin treatment selectively decreased proliferation and increased apoptosis of DIPG cells and significantly extended survival in DIPG xenograft models, while restoring H3K27me3 levels. Moreover, the loss of H3K9 methyltransferase SUV39H1 inhibited DIPG cell growth. Transcriptomic and epigenomic profiling indicated that SUV39H1 loss or inhibition led to the downregulation of stemness and oncogenic networks including growth factor receptor signaling and stemness-related programs; however, D2 dopamine receptor (DRD2) signaling adaptively underwent compensatory upregulation conferring resistance. Consistently, a combination of chaetocin treatment with a DRD2 antagonist ONC201 synergistically increased the antitumor efficacy. CONCLUSIONS: Our studies reveal a therapeutic vulnerability of DIPG cells through targeting the SUV39H1-H3K9me3 pathway and compensatory signaling loops for treating this devastating disease. Combining SUV39H1-targeting chaetocin with other agents such as ONC201 may offer a new strategy for effective DIPG treatment.

H3 K27M-altered glioma and diffuse intrinsic pontine glioma: Semi-systematic review of treatment landscape and future directions.

H3 K27M-mutant diffuse glioma is a recently identified brain tumor associated with poor prognosis. As of 2016, it is classified by the World Health Organization as a distinct form of grade IV glioma. Despite recognition as an important prognostic and diagnostic feature in diffuse glioma, radiation remains the sole standard of care and no effective systemic therapies are available for H3K27M mutant tumors. This review will detail treatment interventions applied to diffuse midline glioma and diffuse intrinsic pontine glioma (DIPG) prior to the identification of the H3 K27M mutation, the current standard-of-care for H3 K27M-mutant diffuse glioma treatment, and ongoing clinical trials listed on www.clinicaltrials.gov evaluating novel therapeutics in this population. Current clinical trials were identified using clinicaltrials.gov, and studies qualifying for this analysis were active or ongoing interventional trials that evaluated a therapy in at least 1 treatment arm or cohort comprised exclusively of patients with DIPG and H3 K27M-mutant glioma. Forty-one studies met these criteria, including trials evaluating H3 K27M vaccination, chimeric antigen receptor T-cell therapy, and small molecule inhibitors. Ongoing evaluation of novel therapeutics is necessary to identify safe and effective interventions in this underserved patient population.

Clinical characteristics and prognostic factors of surgical treatment in children with brainstem tumor.

OBJECTIVE: Brainstem tumors present a significant challenge in surgical treatment, and the prognostic factors in children are lacking. This study aimed to investigate clinical characteristics and prognostic factors of surgical treatment in children with brainstem tumors. PATIENTS AND METHODS: 50 children with brainstem tumors who underwent surgical treatment, including frameless- or frame-based stereotactic biopsy and resection, were included and followed up for clinical and biological analysis. Factors of outcomes were assessed by univariate and multivariate analysis. RESULTS: 27 cases (54.0%) underwent resection in all children with brainstem tumors. The rate of resection reached as high as 81.8% in children with non-diffuse intrinsic pontine glioma (DIPG), while in children with DIPG, biopsy was performed in the majority, and resection was obtained in the minority with focal necrosis. A rare complication was found following the surgery. Multivariate analysis considered World Health Organization (WHO) grade 3-4, with hazard ratio (HR)=4.48, 95% confidence interval (CI) of 2.84-8.69, p=0.001, H3K27M mutation (HR=2.50, 95% CI 1.73-5.69, p=0.015), and hydrocephalus (HR=2.17, 95% CI 1.08-5.32, p=0.014) as independent adverse prognostic factors. For Kaplan-Meier analysis, children with WHO grade 3-4, Ki-67 LI ≥ 20%, TP53 mutation, H3K27M mutation, DIPG, and hydrocephalus had significantly decreased overall survival (OS). CONCLUSIONS: A high rate of resection has been obtained in non-DIPG, and surgical intervention is remarkably safe and efficient for children with brainstem tumors. WHO grade 3-4, H3K27M mutation, and hydrocephalus indicate poor prognosis in children with brainstem tumors.

Recurrent haemorrhagic pontine cavernoma resection via a retrosigmoid microsurgical approach.

BACKGROUND: Brainstem cavernomas occasionally require surgical treatment. Appropriate patient selection and thorough understanding of the anatomy and technical nuances involved in microsurgical resection is a pre-requisite in undertaking these challenging cases. CASE DESCRIPTION: We present a video case of a patient with a recurrent haemorrhagic pontine cavernoma. A step-by-step commentary of surgical footage is provided along with clinical, anatomical and technical learning points pertinent to the safe surgical management of these lesions.

TIM-3 blockade in diffuse intrinsic pontine glioma models promotes tumor regression and antitumor immune memory.

Diffuse intrinsic pontine glioma (DIPG) is an aggressive brain stem tumor and the leading cause of pediatric cancer-related death. To date, these tumors remain incurable, underscoring the need for efficacious therapies. In this study, we demonstrate that the immune checkpoint TIM-3 (HAVCR2) is highly expressed in both tumor cells and microenvironmental cells, mainly microglia and macrophages, in DIPG. We show that inhibition of TIM-3 in syngeneic models of DIPG prolongs survival and produces long-term survivors free of disease that harbor immune memory. This antitumor effect is driven by the direct effect of TIM-3 inhibition in tumor cells, the coordinated action of several immune cell populations, and the secretion of chemokines/cytokines that create a proinflammatory tumor microenvironment favoring a potent antitumor immune response. This work uncovers TIM-3 as a bona fide target in DIPG and supports its clinical translation.

Rapid Peroxide Removal Limits the Radiosensitization of Diffuse Intrinsic Pontine Glioma (DIPG) Cells by Pharmacologic Ascorbate.

Diffuse intrinsic pontine gliomas (DIPG) are an aggressive type of pediatric brain tumor with a very high mortality rate. Surgery has a limited role given the tumor's location. Palliative radiation therapy alleviates symptoms and prolongs survival, but median survival remains less than 1 year. There is no clear role for chemotherapy in DIPGs as trials adding chemotherapy to palliative radiation therapy have failed to improve survival compared to radiation alone. Thus, there is a critical need to identify tissue-specific radiosensitizers to improve clinical outcomes for patients with DIPGs. Pharmacologic (high dose) ascorbate (P-AscH-) is a promising anticancer therapy that sensitizes human tumors, including adult high-grade gliomas, to radiation by acting selectively as a generator of hydrogen peroxide (H2O2) in cancer cells. In this study we demonstrate that in contrast to adult glioma models, P-AscH- does not radiosensitize DIPG. DIPG cells were sensitive to bolus of H2O2 but have faster H2O2 removal rates than GBM models which are radiosensitized by P-AscH-. These data support the hypothesis that P-AscH- does not enhance DIPG radiosensitivity, likely due to a robust capacity to detoxify and remove hydroperoxides.

Role of endoscopic third ventriculostomy in patients undergoing resection of pulvinar area lesions: Preliminary clinical results.

BACKGROUND: Patients with pulvinar area lesions may develop hydrocephalus at any stage. The role of endoscopic third ventriculostomy (ETV) in this setting remains unclear. METHOD: We retrospectively enrolled 15 patients with a mean age of 43 years who underwent endoscopic resection of pulvinar area lesions using the supracerebellar infratentorial approach (SCITA). We compared the different modalities of hydrocephalus management and their outcomes. RESULTS: Nine of 15 patients (60.0%) had preoperative obstructive hydrocephalus. Five patients underwent ETV before tumor resection, and none developed postoperative hydrocephalus. Four patients underwent one-stage surgery for tumor removal, and one patient with a polymorphous low-grade neuroepithelial tumor of the young required postoperative ETV. Another patient with diffuse astrocytoma and hydrocephalus underwent concurrent lamina terminalis fenestration and endoscopic resection via the SCITA, which resulted in the resolution of hydrocephalus. The preoperative ETV group had no major postoperative complications, while the non-ETV group had three (0/5 vs. 3/4, P = 0.048). The ETV group also had a shorter intensive care unit stay; however, the difference was not significant (1.2 vs. 2.8; P = 0.188). ETV was effective in alleviating symptoms of postoperative hydrocephalus in patients with midbrain-invading tumors. CONCLUSION: Endoscopic surgery via the SCITA can address both tumor and hydrocephalus issues in some cases but has a higher surgical risk and postoperative hydrocephalus rate. Preoperative ETV can prevent these complications and improve postoperative outcomes.

Survival and neurological outcomes after stereotactic biopsy of diffuse intrinsic pontine glioma: a systematic review.

OBJECTIVE: Diffuse intrinsic pontine gliomas (DIPGs) are aggressive and malignant tumors of the brainstem. Stereotactic biopsy can obtain molecular and genetic information for diagnostic and potentially therapeutic purposes. However, there is no consensus on the safety of biopsy or effect on survival. The authors aimed to characterize neurological risk associated with and the effect of stereotactic biopsy on survival among patients with DIPGs. METHODS: A systematic review was performed in accordance with PRISMA guidelines to identify all studies examining pediatric patients with DIPG who underwent stereotactic biopsy. The search strategy was deployed in PubMed, Embase, and Scopus. The quality of studies was assessed using the Grading of Recommendations, Assessment, Development and Evaluation system, and risk of bias was evaluated with the Cochrane Risk of Bias in Nonrandomized Studies-of Interventions tool. Bibliographic, demographic, clinical, and outcome data were extracted from studies meeting inclusion criteria. RESULTS: Of 2634 resultant articles, 13 were included, representing 192 patients undergoing biopsy. The weighted mean age at diagnosis was 7.5 years (range 0.5-17 years). There was an overall neurosurgical complication rate of 13.02% (25/192). The most common neurosurgical complication was cranial nerve palsy (4.2%, 8/192), of which cranial nerve VII was the most common (37.5%, 3/8). The second most common complication was perioperative hemorrhage (3.6%, 7/192), followed by hemiparesis (2.1%, 4/192), speech disorders (1.6%, 3/192) such as dysarthria and dysphasia, and movement disorders (1.0%, 2/192). Hydrocephalus was less commonly reported (0.5%, 1/192), and there were no complications relating to wound infection/dehiscence (0%, 0/192) or CSF leak (0%, 0/192). No mortality was specifically attributed to biopsy. Diagnostic yield of biopsy revealed a weighted mean of 97.4% (range 91%-100%). Of the studies reporting survival data, 37.6% (32/85) of patients died within the study follow-up period (range 2 weeks-48 months). The mean overall survival in patients undergoing biopsy was 9.73 months (SD 0.68, median 10 months, range 6-13 months). CONCLUSIONS: Children with DIPGs undergoing biopsy have mild to moderate rates of neurosurgical complications and no excessive morbidity. With reasonably acceptable surgical risk and high diagnostic yield, stereotactic biopsy of DIPGs can allow for characterization of patient-specific molecular and genetic features that may influence prognosis and the development of future therapeutic strategies.