Characteristics and management of hydrocephalus in adult patients with cerebellar glioblastoma: lessons from a French nationwide series of 118 cases

A common tumour in a rare location: a single centre case series of cerebellar glioblastoma

Although glioblastoma is the commonest primary brain tumour in adults, its location in the cerebellum is extremely rare. We present thirteen cases (3 female, 10 male; median age at presentation 56 [age range 21-77]) of surgically managed, histologically confirmed, primary cerebellar glioblastoma (cGB) over a 17 year period (2005-2022). Pre-operative radiological diagnosis was challenging given cGB rarity, although MRI demonstrated ring enhancement in all cases. Surgical management included posterior fossa craniectomy and debulking in 11 cases and burr hole biopsy in two. CSF diversion was necessary in four cases. No evidence of IDH or ATRX gene mutations was found when tested. Survival ranged from 1 to 22 months after diagnosis (mean 10.9 months). We also seek to understand why glioblastoma is rare in this location and discuss potential reasons for this. We hypothesise that increasing anatomical distance from germinal regions and decreased local endogenous neural stem cell activity (which has been associated with glioblastoma) may explain why glioblastoma is rare in the cerebellum. We hereby seek to add to the limited literature on cGB as this is the largest UK cGB series to date.

Clinical course of ventriculoperitoneal shunting for hydrocephalus following glioblastoma surgery: a systematic review and meta-analysis

BACKGROUND

Surgical resection of glioblastoma (GBM) remains a cornerstone in the current treatment paradigm. The postoperative evolution of hydrocephalus necessitating ventriculoperitoneal shunting (VPS) continues to be defined. Correspondingly the objective of this study was to aggregate pertinent metadata to better define the clinical course of VPS for hydrocephalus following glioblastoma surgery in light of contemporary management.

METHODS

Searches of multiple electronic databases from inception to November 2023 were conducted following PRISMA guidelines. Articles were screened against pre-specified criteria. Outcomes were pooled by random-effects meta-analyses where possible.

RESULTS

A total of 12 cohort studies satisfied all selection criteria, describing a total of 6,098 glioblastoma patients after surgery with a total of 261 (4%) of patients requiring postoperative VPS for hydrocephalus. Meta-analysis demonstrated the estimated pooled rate of symptomatic improvement following VPS was 78% (95% CI 66-88), and the estimated pooled rate of VPS revision was 24% (95% CI 16-33). Pooled time from index glioblastoma surgery to VPS surgery was 4.1 months (95% CI 2.8-5.3), and pooled survival time for index VPS surgery was 7.3 months (95% CI 5.4-9.4). Certainty of these outcomes were limited by the heterogenous and palliative nature of postoperative glioblastoma management.

CONCLUSIONS

Of the limited proportion of glioblastoma patients requiring VPS surgery for hydrocephalus after index surgery, 78% patients are expected to show symptom improvement, and 24% can expect to undergo revision surgery. An individualized approach to each patient is required to optimize both index glioblastoma and VPS surgeries to account for anatomy and goals of care given the poor prognosis of this tumor overall.

An integrative survival analysis and a systematic review of the cerebellopontine angle glioblastomas

Glioblastomas presenting topographically at the cerebellopontine angle (CPA) are exceedingly rare. Given the specific anatomical considerations and their rarity, overall survival (OS) and management are not discussed in detail. The authors performed an integrative survival analysis of CPA glioblastomas. A literature search of PubMed, Scopus, and Web of Science databases was performed per PRISMA guidelines. Patient data including demographics, clinical features, neuroimaging, management, follow-up, and OS were extracted. The mean age was 39 ± 26.2 years. The mean OS was 8.9 months. Kaplan-Meier log-rank test and univariate Cox proportional-hazards model identified hydrocephalus (log-rank, p = 0.034; HR 0.34; 95% CI 0.12-0.94; p = 0.038), chemotherapy (log-rank, p < 0.005; HR 5.66; 95% CI 1.53-20.88; p = 0.009), and radiotherapy (log-rank, p < 0.0001; HR 12.01; 95% CI 3.44-41.89; p < 0.001) as factors influencing OS. Hydrocephalus (HR 3.57; 95% CI 1.07-11.1; p = 0.038) and no adjuvant radiotherapy (HR 0.12; 95% CI 0.02-0.59; p < 0.01) remained prognostic on multivariable analysis with fourfold and twofold higher risk for the time-related onset of death, respectively. This should be considered when assessing the risk-to-benefit ratio for patients undergoing surgery for CPA glioblastoma.

Molecular Characterization of Adult Tumors Diagnosed as Cerebellar Glioblastomas Identifies Subgroups Associated With Prognosis

Adult tumors diagnosed as cerebellar glioblastoma (cGBM) are rare and their optimal classification remains to be determined. The aim of this study was to identify subgroups of cGBM based on targeted molecular analysis. cGBM diagnosed between 2003 and 2017 were identified from the French Brain Tumor Database and reviewed according to the WHO 2021 classification. The following molecular alterations were studied: IDH1/2 , H3F3A , FGFR1 , BRAF , TERT promoter mutations, EGFR amplification, MGMT promoter methylation, and alternative lengthening of telomere status. DNA methylation profile was assessed in a subset of cases. Eighty-three cGBM were included and could be classified into 6 mutually exclusive subgroups associated with median age at diagnosis (MA) and prognosis: TERT -mutant and/or EGFR -amplified tumors (n=22, 26.5%, MA=62 y, median overall survival [OS]=4 mo), H3K27M-mutant tumors (n=15, 18.1%, MA=48 y, median OS=8 mo), mitogen-activated protein kinases (MAPK) pathway-activated tumors ( FGFR1 , BRAF mutation, or occurring in neurofibromatosis type I patients, n=15, 18.1%, MA=48 y, median OS=57 mo), radiation-associated tumors (n=5, 6%, MA=47 y, median OS=5 mo), IDH-mutant tumors (n=1), and unclassified tumors (n=25, 30.1%, MA=63 y, median OS=17 mo). Most MAPK pathway-activated tumors corresponded to high-grade astrocytomas with piloid features based on DNA methylation profiling. In multivariate analysis, MAPK pathway-activating alterations, ATRX loss of expression, and alternative lengthening of telomere positivity were independently associated with a better outcome and TERT / EGFR alterations with a worse outcome. cGBM display an important intertumoral heterogeneity. Targeted molecular analysis enables to classify the majority of tumors diagnosed as cGBM into mutually exclusive and clinically relevant subgroups. The presence of MAPK pathway alterations is associated with a much better prognosis.

Value of CSF-Cl, CSF-GS, CSF-MALB, and CSF-ADA in Differential Diagnosis of Secondary Hydrocephalus

Objectives

To investigate the value of cerebrospinal fluid chloride (CSF-Cl), cerebrospinal fluid glucose (CSF-GS), cerebrospinal fluid microalbumin (CSF-MALB), and cerebrospinal fluid adenosine deaminase (CSF-ADA) in the differential diagnosis of secondary hydrocephalus.

Methods

103 patients with secondary hydrocephalus treated in our hospital from January 2018 to April 2022 were selected. According to different types, it is divided into the hemorrhagic hydrocephalus group and tumor hydrocephalus group. By detecting the levels of inflammatory factors such as CSF-Cl, CSF-GS, CSF-MALB, and CSF-ADA in the two groups, we can analyze the value of these inflammatory factors in the differential diagnosis of secondary hydrocephalus.

Results

The level of CSF-MALB in the hemorrhagic hydrocephalus group was significantly higher than that in the tumor hydrocephalus group, and the difference between the two groups was statistically significant (P < 0.05). There was no significant difference in the levels of CSF-Cl, CSF-GS, and CSF-ADA between the two groups (P > 0.05). The area under ROC curve (AUC) of CSF-Cl, CSF-GS, CSF-MALB, and CSF-ADA in the differential diagnosis of secondary hydrocephalus was 0.438, 0.553, 0.750, and 0.542, respectively, sensitivity was 15.1%, 45.3%, 79.2%, and 18.9%, respectively, and specificity was 96.0%, 80.0%, 80.0%, and 94.0%, respectively.

Conclusions

The inflammatory reaction of hemorrhagic hydrocephalus was significantly greater than that of tumor hydrocephalus. Moreover, CSF-MALB is closely related to the pathogenesis of hemorrhagic hydrocephalus. At the same time, CSF-MALB can be used as a good index for rapid differential diagnosis of secondary hydrocephalus.