Glioma tectal pediátrico con hidrocefalia y ventriculomegalia. Dos casos clínicos / Pediatric tectal glioma presented with acute hydrocephalus and ventriculomegaly. Two case reports

Los gliomas tectales representan un subtipo de tumores de bajo grado que se desarrollan en la región tectal, en la parte superior del tronco encefálico. Los síntomas incluyen los causados por el aumento de la presión intracraneal por hidrocefalia obstructiva. Son comunes la cefalea, la visión borrosa o doble, las náuseas y los vómitos. El tratamiento de la hidrocefalia es la ventriculostomía endoscópica del tercer ventrículo o la derivación ventrículo-peritoneal. Los gliomas tectales se diagnostican habitualmente en la infancia, pero son frecuentes también en adultos. En general son benignos y de progresión lenta; es suficiente el seguimiento ambulatorio clínico y radiológico. Se presentan dos pacientes pediátricos con tumores de la placa tectal mesencefálica. Un niño de 11 años y una niña de 15 años concurrieron al Departamento de Emergencias con diferentes síntomas. El niño fue tratado con derivación ventrículo-peritoneal por hidrocefalia aguda.

Tectal gliomas represent a subset of low-grade tumors that arise in the tectal region at the roof of the brainstem. Symptoms of tectal glioma include those caused by increased intracranial pressure due to obstructive hydrocephalus. Headache, blurred vision, double vision, nausea and vomiting are common symptoms. In the treatment, ETV (endoscopic third ventriculostomy) or VP-shunt (ventriculoperitoneal) can be applied to treat hydrocephalus. Tectal gliomas are usually diagnosed in childhood and often occur in adults. They are often benign, slowly progressing lesions; outpatient clinical and radiological followup is sufficient. We present two cases of pediatric patients with mesencephalic tectal plate tumors. An 11-year-old boy and a 15-year-old girl applied to the Emergency Department with different complaints. The 11 year-old-boy was treated with VP-shunt due to acute hydrocephalus.

Assessment of histogram analysis in distinguishing between low-grade and high-grade brainstem glioma.

Objectives: This retrospective study was designed to evaluate the value of histogram analysis on the apparent diffusion coefficient (ADC) map in distinguishing between low-grade and high-grade brainstem glioma (BSG). In this article, we used the two VOI (volume of interest) placements of the entire tumour method and the entire solid part method, thus aiming to compare the diagnostic value between these two performances. Methods: A total of 28 patients (8 low-grade BSGs and 20 high-grade BSGs) with histological diagnosis of BSG. All victims underwent contrast-enhanced magnetic resonance imaging (MRI). We measured ADC histogram parameters (mean, median, SD, max, min, Kurtosis, Skewness, Entropy, Uniformity, and Variance) and calculated the ratios between tumour and normal brain parenchyma parameters in two methods. Independent samples test, Mann-Whitney U test, and ROC curve were used to determine each value's cut-off point, sensitivity, and specificity. Results: Among the method of VOI placing the entire tumour, the values of ADC_min, rADC_mean, rADC_median, and rADC_min are significantly different between these two neoplasms with cut-off values (sensitivity %, specificity %) of 776 x10-6 m2/s (62.5%, 90%), 2.1765 (62.5%, 95%), 2.1588 (50%, 100%), 1.0535 (100%, 50%), respectively. On the other hand, the method of VOI placing the entire solid part of the tumour showed significantly different in ADC_mean, ADC_median, ADC_min, rADC_mean, rADC_median, rADC_min at the cut-off values (sensitivity%, specificity %) of 1491 x10-6 m2/s (62.5%, 95%), 1438.9 x10-6 m2/s (62.5%, 90%), 862.5 x10-6 m2/s (75%, 100%), 2,112 (62.5%, 95%), 1.9748 (62.5%, 90%), 1.3735 (87.5%, 90%), respectively. Conclusions: The ADC histogram analysis is a promising approach to distinguishing low-grade BSG and high-grade BSG. The entire solid part VOI placement has a superior value compared to the whole tumour VOI placement. The rADC_mean showed the best performance in differentiating between these two entities, followed by ADC_min, rADC_mean, rADC_median, ADC_mean, and ADC_median.

Management of patients with diffuse intrinsic pontine glioma in Australia and New Zealand: Australian and New Zealand Children's Haematology/Oncology Group position statement.

INTRODUCTION: The main mission of the Australian and New Zealand Children's Haematology and Oncology Group (ANZCHOG) is to develop and facilitate local access to the world's leading evidence-based clinical trials for all paediatric cancers, including brain tumours, as soon as practically possible. Diffuse intrinsic pontine gliomas (DIPGs) - a subset of a larger group of tumours now termed diffuse midline glioma, H3K27-altered (DMG) - are paediatric brain cancers with less than 10% survival at two years. In the absence of any proven curative therapies, significant recent advancements have been made in pre-clinical and clinical research, leading many to seek integration of novel therapies early into standard practice. Despite these innovative therapeutic approaches, DIPG remains an incurable disease for which novel surgical, imaging, diagnostic, radiation and systemic therapy approaches are needed. MAIN RECOMMENDATIONS: All patients with DIPG should be discussed in multidisciplinary neuro-oncology meetings (including pathologists, neuroradiologists, radiation oncologists, neurosurgeons, medical oncologists) at diagnosis and at relapse or progression. Radiation therapy to the involved field remains the local and international standard of care treatment. Proton therapy does not yield a superior survival outcome compared with photon therapy and patients should undergo radiation therapy with the available modality (photon or proton) at their treatment centre. Patients may receive concurrent chemotherapy or radiation-sensitising agents as part of a clinical trial. Biopsy should be offered to facilitate consideration of experimental therapies and eligibility for clinical trial participation. After radiation therapy, each patient should be managed individually with either observation or considered for enrolment on a clinical trial, if eligible, after full discussion with the family. Re-irradiation can be considered for progressive disease. CHANGES IN MANAGEMENT AS A RESULT OF THE GUIDELINE: Every child diagnosed with DIPG should be offered enrolment on a clinical trial where available. Access to investigational drugs without biological rationale outside the clinical trial setting is not supported. In case of potentially actionable target identification with molecular profiling and absence of a suitable clinical trial, rational targeted therapies can be considered through compassionate access programs.

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.

Symptomatic infratentorial ependymal cyst arising from the medulla: a case report with review of literature.

BACKGROUND: Ependymal cysts (EC) typically present supra-tentorially near the lateral ventricle, juxta ventricular, or temporoparietal regions. Previous cases have also identified infratentorial EC of the brainstem, cerebellum, and subarachnoid spaces. They are mostly asymptomatic. In this paper, we present the first-ever case of a symptomatic medullary ependymal cyst treated with surgery, along with a comprehensive review of the literature on EC of other parts of the brain stem. CASE DESCRIPTION: This 51-year-old female presented with hearing loss, dizziness, diplopia, and ataxia. Radiographic imaging indicated the presence of a non-enhancing lesion in the medulla with a mass effect on the brainstem. Pathological examination confirmed its characterization as an ependymal cyst. The patient underwent a suboccipital craniotomy for the fenestration of the medullary ependymal cyst under neuro-navigation, Intra-op ultrasound and intra-operative neuro-monitoring. Histopathological examination confirmed the diagnosis of an ependymal cyst. At one month follow-up, her KPS is 90, ECOG PS 1, and her ataxia has improved with complete resolution of diplopia. CONCLUSION: Due to their rarity and potential similarity to other cystic structures, EC may be overlooked or incorrectly diagnosed resulting in mismanagement and surgical disaster. Therefore, a comprehensive understanding and awareness of their distinct characteristics are essential for accurate diagnosis and appropriate management.

Pediatric tectal glioma presented with acute hydrocephalus and ventriculomegaly. Two case reports. / Glioma tectal pediátrico con hidrocefalia y ventriculomegalia. Dos casos clínicos.

Tectal gliomas represent a subset of low-grade tumors that arise in the tectal region at the roof of the brainstem. Symptoms of tectal glioma include those caused by increased intracranial pressure due to obstructive hydrocephalus. Headache, blurred vision, double vision, nausea and vomiting are common symptoms. In the treatment, ETV (endoscopic third ventriculostomy) or VP-shunt (ventriculoperitoneal) can be applied to treat hydrocephalus. Tectal gliomas are usually diagnosed in childhood and often occur in adults. They are often benign, slowly progressing lesions; outpatient clinical and radiological follow- up is sufficient. We present two cases of pediatric patients with mesencephalic tectal plate tumors. An 11-year-old boy and a 15-year-old girl applied to the Emergency Department with different complaints. The 11 year-old-boy was treated with VP-shunt due to acute hydrocephalus.

Los gliomas tectales representan un subtipo de tumores de bajo grado que se desarrollan en la región tectal, en la parte superior del tronco encefálico. Los síntomas incluyen los causados por el aumento de la presión intracraneal por hidrocefalia obstructiva. Son comunes la cefalea, la visión borrosa o doble, las náuseas y los vómitos. El tratamiento de la hidrocefalia es la ventriculostomía endoscópica del tercer ventrículo o la derivación ventrículo-peritoneal. Los gliomas tectales se diagnostican habitualmente en la infancia, pero son frecuentes también en adultos. En general son benignos y de progresión lenta; es suficiente el seguimiento ambulatorio clínico y radiológico. Se presentan dos pacientes pediátricos con tumores de la placa tectal mesencefálica. Un niño de 11 años y una niña de 15 años concurrieron al Departamento de Emergencias con diferentes síntomas. El niño fue tratado con derivación ventrículo-peritoneal por hidrocefalia aguda.

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.

A decade of treating brain stem gliomas: Single institutional experience.

INTRODUCTION: Brainstem is a rare yet challenging site for primary brain tumors. We present the patient characteristics, treatment-related details, and survival outcomes of patients with brain stem gliomas treated over a decade, from August 2010 to July 2022, at a tertiary care center in northern India. MATERIALS AND METHODS: Twenty-seven patients of brainstem gliomas were treated in our hospital from August 2010 to July 2022. All of these patients were treated with radiation therapy based on a radiological diagnosis only. Data were collected and analyzed from patient registration, treatment, and follow-up records. RESULTS: Of the 27 patients, 18 were male and 9 were female. Fourteen patients (51.85%) were in the pediatric age group (<12 years). The most common symptom at onset was hemiparesis, seen in 62.96%. The majority of the patients (24; 88.88%) had pontine involvement at the time of treatment. Overall survival at a minimum 2-year follow-up post-treatment was 22.22% in the entire cohort. Age, sex, or size of tumor at presentation was not seen to have any significant impact on survival of patients. CONCLUSION: With the advancement in surgical techniques and molecular analysis of brain tumors, there is likely to be a change in the management of brainstem gliomas; however, radiation therapy has been used for the management of these tumors for decades now. Radiation therapy continues to show rapid and significant radiological and clinical improvement in the majority of such patients, and it would continue to play an important part in multi-modality management.

Oncolytic virotherapy for the treatment of pediatric brainstem gliomas.

Diffuse intrinsic pontine glioma (DIPG) is the most frequent brainstem glioma and the most lethal brain tumor in childhood. Despite transient benefit with radiotherapy, the prognosis of children with this disease remains dismal with severe neurological morbidity and median survival less than 12months. Oncolytic immunovirotherapy is emerging as a potential therapeutic approach in neuro-oncology. The oncolytic adenovirus Delta-24-RGD has shown efficacy in adult patients with recurrent GBM. Our group has demonstrated that Delta-24-RGD has oncolytic activity and triggers immune response in preclinical models of DIPG, and has a synergistic effect with radiotherapy in animal models of this disease. In this scenario, we conducted a first-in-human phase 1 clinical trial to evaluate the safety and efficacy of intratumoral injection of Delta-24-RGD in pediatric patients with newly diagnosed DIPG prior to standard radiotherapy. The study confirmed the feasibility of this treatment with an acceptable safety profile and encouraging efficacy results. Correlative analyses showed a biological activity from Delta-24-RGD in DIPG. Further advanced trials are needed to validate these results. Meanwhile, plenty of opportunities to increase the potential contribution of oncolytic viruses in the management of devastating tumors with no current effective treatment such as DIPG need to be explored and exploited.

Atypical Molecular Features of Pediatric Tectal Glioma: A Single Institutional Series.

We present 4 children (diagnosed between 1 and 8 y, 3 females and 1 male) with molecularly distinct tectal gliomas (2 KRAS mutant, 1 EGFR mutant, 1 SRGAP3-RAF-1 fusion) that contributes to the growing literature of this uncommonly biopsied tumor. The patient with EGFR R222C mutation had a more severe course, earlier diagnosis, subsequent leptomeningeal metastatic disease, required more aggressive therapies, and died 9 years after diagnosis. Patients with KRAS mutations and SRGAP3-RAF-1 fusion had a more indolent course. Our series expands the molecular phenotype of tectal glioma with the potential for leptomeningeal dissemination. Future studies on establishing genotypic/phenotypic correlation from those who undergo biopsy are needed.

Past, present and future of Focused Ultrasound as an adjunct or complement to DIPG/DMG therapy: A consensus of the 2021 FUSF DIPG meeting.

Diffuse Intrinsic Pontine Glioma (DIPG), now known as Diffuse Midline Glioma (DMG) is a devastating pediatric brain tumor with limited treatment options and a very poor prognosis. Despite more than 250 clinical trials aimed to treat children diagnosed with DMG, no curative therapies currently exist for this patient population. A major obstacle has been the intact blood brain barrier (BBB) which prevents most therapeutics from crossing into the tumor bed. Focused Ultrasound (FUS) is an emerging, noninvasive medical technology which has been shown in both preclinical and clinical research to disrupt the blood brain barrier safely and temporarily. FUS blood brain barrier opening has been studied in combination with chemotherapies in preclinical DMG models, and this technology is now being investigated in clinical trials for the treatment of pediatric brain tumors. Focused ultrasound has additional mechanisms of action, including sonodynamic therapy and radiation sensitization, that hold promise as future DMG therapies as well. This paper, largely based off the proceedings from a workshop held by the Focused Ultrasound Foundation in October of 2021, summarizes the current state of the field of focused ultrasound for DIPG/DMG, including preclinical, technical, and clinical summaries in addition to recommended next steps for continued advancement of the game changing technology of Focused Ultrasound.

[Formula: see text] The neuropsychological profile of children with Diffuse Intrinsic Pontine Glioma (DIPG) before and after radiation therapy: A prospective longitudinal study.

Children with Diffuse Intrinsic Pontine Gliomas (DIPG), a malignant brainstem tumor, experience poor prognosis. Because of the disease's rarity and highly aggressive course, there is a dearth of research on cognitive and psychosocial outcomes in this underserved, vulnerable population. However, evaluating effects of the disease and treatment on the cognitive and daily functioning of these patients is important to better understand their specific needs and improve their quality of life. The current longitudinal study administered prospective neuropsychological assessments to children diagnosed with CNS malignancies, including the largest sample of children with DIPG to date (n = 21, mean age = 7.86 years, range = 3-16) in neurocognitive, behavioral, social-emotional, and adaptive functioning at baseline, two weeks post-radiation, and six months later. The results describe population-based, cross-sectional characteristics and within-patient longitudinal changes. Prior to radiation, children with DIPG exhibited significant weaknesses compared to normative samples in both parent-report and performance-based measures of attention, and tests of processing speed and verbal learning/memory. Younger children demonstrated poorer inhibitory control on performance tests and worse parent-reported behavioral regulation, depression, and social withdrawal compared to older children. Six-months post-radiation, older children exhibited poorer socialization than younger children. Longitudinally, children with DIPG exhibited short-term improvements immediately post-radiation in performance-based attention tests and parent-reported behavior, including attention, hyperactivity, behavioral regulation, and executive function. However, these improvements did not persist and significant decline was documented on tests of attention by six months. Clinical implications for professionals working with children with DIPG and recommendations for cognitive remediation and quality of life interventions are provided.

Endoscopic transventricular biopsy in brainstem diffuse midline glioma: how I do it.

BACKGROUND: Brainstem diffuse midline gliomas represent infiltrative and rare pediatric tumors with a dismal prognosis. Surgical biopsy is emerging as a valid technique to define diagnosis and molecular markers for future targeted therapies. METHOD: We describe the key steps of an endoscopic trans-ventricular biopsy of a brainstem diffuse midline glioma and associated ventriculomegaly. The relevant surgical anatomy along with an illustrative video is described. CONCLUSION: The endoscopic third ventriculostomy combined with a punch biopsy of a brainstem diffuse midline glioma associated with ventriculomegaly represent a feasible and low-risk procedure to simultaneously treat incipient hydrocephalus and molecular diagnosis for future treatment and research.

A homogeneous treatment for non-DIPG diffuse midline glioma.

INTRODUCTION: The H3K27M-mutant diffuse midline glioma (DMG) was first included in the World Health Organization (WHO) Classification of central nervous system (CNS) tumors in 2016, and confirmed in its fifth edition. The biological behavior and dismal prognosis of this tumor resemble diffuse intrinsic pontine gliomas (DIPG). Homogeneously-treated series are rarely reported. METHODS: From 2016 onwards, we treated patients with DMG with radiotherapy and concomitant/adjuvant nimotuzumab/vinorelbine, plus re-irradiation at relapse, as already done for DIPG. RESULTS: We treated nine patients, seven females, with a median age at diagnosis of 13 years. Tumor sites were: thalamic in five cases, pontocerebellar in two, pineal in one, and paratrigonal with nodular/leptomeningeal dissemination in one. Three patients were biopsied, and six had partial tumor resections. Central pathological review was always performed. The median time to local progression was 12.7 months, and the median overall survival was 17.8 months. Six patients died of tumor progression, one of cerebral bleeding at progression. Two were alive, one in continuous remission, the other after relapsing, at 38.6 and 46.3 months after diagnosis. Progression-free survival was 33.3% at one year. Overall survival was 88.9%, 33.3% and 22.2% at 1, 2 and 3 years, respectively. CONCLUSIONS: This is a small series of homogeneously-treated DMG patients. The results obtained are comparable with those of DIPG patients. Given the phenotypically- and molecularly-defined setting of DMG and severe outcome in this orphan population, they should be treated and included in registries and protocols of DIPG.

Suggestions for Escaping the Dark Ages for Pediatric Diffuse Intrinsic Pontine Glioma Treated with Radiotherapy: Analysis of Prognostic Factors from the National Multicenter Study.

PURPOSE: This multicenter retrospective study aimed to investigate clinical, radiologic, and treatment-related factors affecting survival in patients with newly diagnosed diffuse intrinsic pontine glioma (DIPG) treated with radiotherapy. MATERIALS AND METHODS: Patients aged <30 years who underwent radiotherapy as an initial treatment for DIPG between 2000 and 2018 were included; patients who did not undergo magnetic resonance imaging at diagnosis and those with pathologically diagnosed grade I glioma were excluded. We examined medical records of 162 patients collected from 10 participating centers in Korea. The patients' clinical, radiological, molecular, and histopathologic characteristics, and treatment responses were evaluated to identify the prognosticators for DIPG and estimate survival outcomes. RESULTS: The median follow-up period was 10.8 months (interquartile range, 7.5 to 18.1). The 1- and 2-year overall survival (OS) rates were 53.5% and 19.0%, respectively, with a median OS of 13.1 months. Long-term survival rate (≥ 2 years) was 16.7%, and median OS was 43.6 months. Age (< 10 years), poor performance status, treatment before 2010, and post-radiotherapy necrosis were independently associated with poor OS in multivariate analysis. In patients with increased post-radiotherapy necrosis, the median OS estimates were 13.3 months and 11.4 months with and without bevacizumab, respectively (p=0.138). CONCLUSION: Therapeutic strategy for DIPG has remained unchanged over time, and the associated prognosis remains poor. Our findings suggest that appropriate efforts are needed to reduce the occurrence of post-radiotherapy necrosis. Further well-designed clinical trials are recommended to improve the poor prognosis observed in DIPG patients.

Interdisciplinary care of children with diffuse midline glioma.

Diffuse Midline Glioma (DMG) which includes Diffuse Intrinsic Pontine Glioma (DIPG) is an infiltrative tumor of the midline structures of the central nervous system that demonstrates an aggressive pattern of growth and has no known curative treatment. As these tumors progress, children experience ongoing neurological decline including inability to ambulate, swallow and communicate effectively. We propose that optimal care for patients with DMG should involve a specialized team experienced in caring for the multifaceted needs of these patients and their families. Herein we review the roles and evidence to support early involvement of a specialized interdisciplinary team and outline our views on best practices for these challenging tumors.

Trigeminal trophic syndrome in a pediatric patient with diffuse intrinsic pontine glioma.

A 13-year-old girl with a history of diffuse intrinsic pontine glioma (DIPG) suffered from progressively worsening facial ulcerations secondary to paresthesia-induced self-excoriation. She was diagnosed with trigeminal trophic syndrome (TTS) induced by DIPG and struggled to heal her lesions in the background of this excoriation disorder. A multidisciplinary approach that included mood disorder management with sertraline and amitriptyline helped diminish paresthesia, improve her quality of life, and promote healing of the ulcers despite the progression of her DIPG. This case highlights the multifactorial complexity of TTS in pediatric patients and the need for successful management strategies.

Biopsy of paediatric brainstem intrinsic tumours: Experience from a Singapore Children's Hospital.

BACKGROUND: Biopsy of intrinsic brainstem tumours presumed to be diffuse midline gliomas (previously known as DIPG) is controversial. Surgery has risks of injury to the eloquent brainstem and may not have direct benefit to the patient. Technological improvements in operative adjuncts have allowed the role of biopsy for paediatric brainstem lesions to be revisited with new insights. This study aims to evaluate our institutional experience in brainstem biopsy. METHODS: This is an ethics-approved retrospective study based in KK Women's and Children's Hospital. Patients diagnosed with intrinsic brainstem tumours and managed by the Neurosurgical Service were included. Variables of interest included patient demographics, neuroimaging features, type of surgery, histological and molecular diagnosis, treatment, and outcomes. RESULTS: From 2006 to 2021, a total of 27 brainstem intrinsic tumours were referred to the Neurosurgical Service. Eleven (40.7 %) patients underwent stereotactic biopsy and 10 (37 %) had open biopsies. Histologically, 10 (37 %) were confirmed to be high grade gliomas, eight (29.6 %) were low grade gliomas and 3 (11.1 %) were malignant embryonal tumours. No negative diagnostic results or permanent postoperative complications were encountered. Five patients went on to have their tumours interrogated via next-generation sequencing to look for targetable mutations. The remaining 6 (22.2 %) patients did not undergo biopsy, whereby 1 of them is still alive after 6 years. CONCLUSION: Biopsy of paediatric brainstem intrinsic tumours is a safe procedure that concurrs with accurate tissue diagnosis. This option can be offered to affected patients, especially to identify relevant markers for targeted therapy.

Roles and outcomes of stereotactic biopsy for adult patients with brainstem lesion.

PURPOSE: This study aimed to assess the benefit-risk ratio by determining diagnostic yield and safety of brainstem biopsies in adult patients. The secondary objectives were (i) to compare brainstem biopsy safety and postbiopsy patients' outcomes and survival with those of patients biopsied for a brain or cerebellar lesion, and (ii) to assess the impact of brainstem biopsy on final diagnosis and further therapeutic management. METHODS: Among 1784 stereotactic biopsies performed in adult patients at a tertiary center between April 2009 and October 2020, we retrospectively examined 50 consecutive brainstem biopsies. We compared variables regarding diagnostic yield, safety and post-biopsy outcomes between brainstem biopsy patients and brain/cerebellum biopsy patients. RESULTS: Brainstem biopsy led to a diagnosis in 86% of patients (94.6% in patients with suspected tumor). Lesion contrast enhancement on imaging was the sole predictor of obtaining a diagnosis. Rates of symptomatic complications and mortality were significantly higher in brainstem biopsy patients compared to brain/cerebellum biopsy patients (20% vs 0%; p < 0.001 and 6% vs 0%; p = 0.01, respectively). Transfrontal trajectory and prebiopsy swallowing disorders were predictors of brainstem biopsy-related symptomatic complications. Brainstem biopsy findings led to diagnostic change in 22% of patients. CONCLUSIONS: Stereotactic biopsy in adult patients with brainstem lesion has a high diagnostic yield. Although stereotactic brainstem biopsy is associated with more functional and fatal complications than biopsies targeting the brain/cerebellum, its safety profile appears acceptable. Thus, the benefit-risk ratio of stereotactic biopsy in patients with brainstem lesion is favorable but should nevertheless be carefully weighted on a case-by-case basis.