Endoscopic third ventriculostomy for hydrocephalus associated with tectal gliomas

Pediatric and Adult Low-Grade Gliomas: Where Do the Differences Lie?

Two thirds of pediatric gliomas are classified as low-grade (LGG), while in adults only around 20% of gliomas are low-grade. However, these tumors do not only differ in their incidence but also in their location, behavior and, subsequently, treatment. Pediatric LGG constitute 65% of pilocytic astrocytomas, while in adults the most commonly found histology is diffuse low-grade glioma (WHO II), which mostly occurs in eloquent regions of the brain, while its pediatric counterpart is frequently found in the infratentorial compartment. The different tumor locations require different skillsets from neurosurgeons. In adult LGG, a common practice is awake surgery, which is rarely performed on children. On the other hand, pediatric neurosurgeons are more commonly confronted with infratentorial tumors causing hydrocephalus, which more often require endoscopic or shunt procedures to restore the cerebrospinal fluid flow. In adult and pediatric LGG surgery, gross total excision is the primary treatment strategy. Only tumor recurrences or progression warrant adjuvant therapy with either chemo- or radiotherapy. In pediatric LGG, MEK inhibitors have shown promising initial results in treating recurrent LGG and several ongoing trials are investigating their role and safety. Moreover, predisposition syndromes, such as neurofibromatosis or tuberous sclerosis complex, can increase the risk of developing LGG in children, while in adults, usually no tumor growth in these syndromes is observed. In this review, we discuss and compare the differences between pediatric and adult LGG, emphasizing that pediatric LGG should not be approached and managed in the same way as adult LCG.

Management strategies for pediatric patients with tectal gliomas: a systematic review

Pediatric tectal gliomas generally have a benign clinical course with the majority of these observed radiologically. However, patients often need treatment for obstructive hydrocephalus and occasionally require cytotoxic therapy. Given the lack of level I data, there is a need to further characterize management strategies for these rare tumors. We have therefore performed the first systematic review comparing various management strategies. The literature was systematically searched from January 1, 2000, to July 30, 2020, to identify studies reporting treatment strategies for pediatric tectal gliomas. The systematic review included 355 patients from 14 studies. Abnormal ocular findings-including gaze palsies, papilledema, diplopia, and visual field changes-were a common presentation with between 13.6 and 88.9% of patients experiencing such findings. CSF diversion was the most performed procedure, occurring in 317 patients (89.3%). In individual studies, use of CSF diversion ranged from 73.1 to 100.0%. For management options, 232 patients were radiologically monitored (65.4%), 69 received resection (19.4%), 30 received radiotherapy (8.4%), and 19 received chemotherapy (5.4%). When examining frequencies within individual studies, chemotherapy ranged from 2.5 to 29.6% and radiotherapy ranged from 2.5 to 28.6%. Resection was the most variable treatment option between individual studies, ranging from 2.3 to 100.0%. Most tectal gliomas in the pediatric population can be observed through radiographic surveillance and CSF diversion. Other forms of management (i.e., chemotherapy and radiotherapy) are warranted for more aggressive tumors demonstrating radiological progression. Surgical resection should be reserved for large tumors and/or those that are refractory to other treatment modalities.

Endoscopic third ventriculostomy for pediatric tumor-associated hydrocephalus

OBJECTIVE

Surgical options for managing hydrocephalus secondary to CNS tumors have traditionally included ventriculoperitoneal shunting (VPS) when tumor resection or medical management alone are ineffective. Endoscopic third ventriculostomy (ETV) has emerged as an attractive treatment strategy for tumor-associated hydrocephalus because it offers a lower risk of infection and hardware-related complications; however, relatively little has been written on the topic of ETV specifically for the treatment of tumor-associated hydrocephalus. Here, the authors reviewed the existing literature on the use of ETV in the treatment of tumor-associated hydrocephalus, focusing on the frequency of ETV use and the failure rates in patients with hydrocephalus secondary to CNS tumor.

METHODS

The authors queried PubMed for the following terms: "endoscopic third ventriculostomy," "tumor," and "pediatric." Papers with only adult populations, case reports, and papers published before the year 2000 were excluded. The authors analyzed the etiology of hydrocephalus and failure rates after ETV, and they compared failure rates of ETV with those of VPS where reported.

RESULTS

Thirty-two studies with data on pediatric patients undergoing ETV for tumor-related hydrocephalus were analyzed. Tumors, particularly in the posterior fossa, were reported as the etiology of hydrocephalus in 38.6% of all ETVs performed (984 of 2547 ETVs, range 29%-55%). The ETV failure rate in tumor-related hydrocephalus ranged from 6% to 38.6%, and in the largest studies analyzed (> 100 patients), the ETV failure rate ranged from 10% to 38.6%. The pooled ETV failure rate was 18.3% (199 failures after 1087 procedures). The mean or median follow-up for ETV failure assessment ranged from 6 months to 8 years in these studies. Only 5 studies directly compared ETV with VPS for tumor-associated hydrocephalus, and they reported mixed results in regard to failure rate and time to failure. Overall failure rates appear similar for ETV and VPS over time, and the risk of infection appears to be lower in those patients undergoing ETV. The literature is mixed regarding the need for routine ETV before resection for posterior fossa tumors with associated hydrocephalus.

CONCLUSIONS

Treatment of tumor-related hydrocephalus with ETV is common and is warranted in select pediatric patient populations. Failure rates are overall similar to those of VPS for tumor-associated hydrocephalus.

Tectal gliomas: assessment of malignant progression, clinical management, and quality of life in a supposedly benign neoplasm

OBJECTIVE Tectal gliomas constitute a rare and inhomogeneous group of lesions with an uncertain clinical course. Because these supposedly benign tumors are frequently followed up by observation over many years, the authors undertook this analysis of their own case series in an effort to demonstrate that the clinical course is highly variable and that there is a potential for a progressive biology. METHODS Clinical data analysis of 23 cases of tectal glioma (involving 9 children and 14 adults) was performed retrospectively. Radiographic data were analyzed longitudinally and MR images were evaluated for tumor volume, contrast enhancement, and growth progression. Quality of life was assessed using the EORTC BN20 and C30 questionnaires during follow-up in a subgroup of patients. RESULTS The patients' mean age at diagnosis was 29.2 years. The main presenting symptom at diagnosis was hydrocephalus (80%). Six patients were treated by primary tumor resection (26.1%), 3 patients underwent biopsy followed by resection (13.1%), and 3 patients underwent biopsy only (13.1%). For additional treatment of hydrocephalus, 14 patients (60.9%) received shunts and/or endoscopic third ventriculostomy. Radiographic tumor progression was observed in 47.9% of the 23 cases. The mean time between diagnosis and growth progression was 51.5 months, and the mean time to contrast enhancement was 69.7 months. Histopathological analysis was obtained in 12 cases (52.2%), resulting in 5 cases of high-grade glioma (3 cases of glioblastoma multiforme [GBM], grade IV, and 2 of anaplastic astrocytoma, grade III), 5 cases of pilocytic astrocytoma, 1 diffuse astrocytoma, and 1 ganglioglioma. Malignant progression was observed in 2 cases, with 1 case progressing from a diffuse astrocytoma (grade II) to a GBM (grade IV) within a period of 13 years. Quality-of-life measurements demonstrated distinct functional deficits compared to a healthy sample as well as glioma control cohorts. CONCLUSIONS Analysis of this case series shows that a major subpopulation of tectal gliomas show progression and malignant transformation in children as well as in adolescents. These tumors therefore cannot be considered inert lesions and require histological confirmation and close follow-up. Quality-of-life questionnaires show that tectal glioma patients might benefit from special psychological support in emotional, social, and cognitive functionality.

Endoscopic third ventriculostomy prior to resection of posterior fossa tumors in children

OBJECTIVE

Hydrocephalus is a common presenting symptom of pediatric posterior fossa tumors and often requires permanent cerebrospinal fluid diversion even after resection. Endoscopic third ventriculostomy (ETV) is a well-established treatment of obstructive hydrocephalus in children. The objective of this study is to demonstrate that ETV prior to posterior fossa tumor resection decreases the rate of postoperative ventriculoperitonal shunt (VPS) placement.

METHODS

We performed a retrospective analysis of patients who presented with hydrocephalus and underwent posterior fossa tumor resection between 2005 and 2016 excluding pineal and tectal tumors. The rate of postoperative VPS placement was compared in patients who underwent resection and had a VPS placed perioperatively (historical controls) with patients who underwent ETV prior to resection. The two groups were matched for demographics, tumor histology, and tumor location. We also performed a literature review of prior studies that examined the role of ETV in pediatric posterior fossa tumors.

RESULTS

Thirty-six patients in the control group were compared to 38 patients in our study. The patients were matched across all variables (age, gender, tumor histology, and tumor locations). The rate of postoperative VPS placement was 31% in the control group compared to 16% in the ETV group. No complications were encountered during ETV.

CONCLUSIONS

Endoscopic third ventriculostomy prior to posterior fossa tumor resection in children appears to decrease the rate of postoperative VPS placement. Given its efficacy and safety, ETV should be considered prior to tumor resection in these patients.

Pediatric Brainstem Gliomas: A Retrospective Study of 180 Patients from the SEER Database

BACKGROUND/AIMS

Large population-based studies are needed to assess the epidemiology and survival risk factors associated with pediatric brainstem gliomas. This retrospective study explores factors that may influence survival in this population.

METHODS

Utilizing the SEER database, the authors retrospectively assessed survival in histologically confirmed brainstem gliomas in patients aged 17 and younger. Survival was described with Kaplan-Meyer curves and multivariate regression analysis.

RESULTS

This analysis of 180 cases showed that age (hazard ratio [HR] 1.04, 95% CI 0.96-1.14, p = 0.34), non-white race (HR 1.00, 95% CI 0.35-2.85 p > 0.99), distant or invasive extension of the tumor (HR 0.4, 95% CI 0.08-2.53, p = 0.37), and radiation therapy (HR 1.27, 95% CI 0.52-3.11, p = 0.61) were not associated with decreased survival. High-grade tumor status (HR 8.64, 95% CI 3.49-21.41, p < 0.001) was associated with decreased survival. Partial resection (HR 0.11, 95% CI 0.04-0.30, p < 0.001) and gross-total resection (HR 0.03, 95% CI 0.01-0.14, p < 0.001) were associated with improved survival.

CONCLUSIONS

High-grade brainstem gliomas have a worse prognosis. Early diagnosis and surgery appear to be associated with improved survival, while the role of radiation is unclear.

Tectal glioma as a distinct diagnostic entity: a comprehensive clinical, imaging, histologic and molecular analysis

Tectal glioma (TG) is a rare low-grade tumor occurring predominantly in the pediatric population. There has been no detailed analysis of molecular alterations in TG. Risk factors associated with inferior outcome and long-term sequelae of TG have not been well-documented. We retrospectively studied TGs treated or referred for review at St. Jude Children’s Research Hospital (SJCRH) between 1986 and 2013. Longitudinal clinical data were summarized, imaging and pathology specimen centrally reviewed, and tumor material analyzed with targeted molecular testing and genome-wide DNA methylation profiling. Forty-five patients with TG were included. Twenty-six (57.8%) were male. Median age at diagnosis was 9.9 years (range, 0.01–20.5). Median follow-up was 7.6 years (range, 0.5–17.0). The most common presenting symptoms were related to increased intracranial pressure. Of the 22 patients treated at SJCRH, 19 (86%) required cerebrospinal fluid diversion and seven (32%) underwent tumor-directed surgery. Five patients (23%) received radiation therapy and four (18%) systemic therapy. Ten-year overall and progression-free survival were 83.9 ± 10.4% and 48.7 ± 14.2%, respectively. Long-term morbidities included chronic headaches, visual symptoms and neurocognitive impairment. Lesion ≥3cm², contrast enhancement and cystic changes at presentation were risk factors for progression. Among those with tumor tissue available, 83% showed growth patterns similar to pilocytic astrocytoma and 17% aligned best with diffuse astrocytoma. BRAF duplication (a marker of KIAA1549-BRAF fusion) and BRAF V600E mutation were detected in 25% and 7.7%, respectively. No case had histone H3 K27M mutation. DNA methylation profile of TG was distinct from other brain tumors. In summary, TG is an indolent, chronic disease with unique clinical and molecular profiles and associated with long term morbidities. Large size, contrast enhancement and cystic changes are risk factors for progression.

Endoscopic Treatment of an Adult with Tegmental Astrocytoma Accompanied by Cerebrospinal Fluid Dissemination

Midbrain gliomas are relatively rare neoplasms with a generally benign prognosis, with dissemination or metastasis not previously reported. We describe here a woman, in whom magnetic resonance imaging scans showed hydrocephalus and a tegmental lesion in the upper aqueduct. Endoscopic third ventriculostomy and biopsy were performed; during surgery, a second small lesion was observed in the infundibular recess. Histologically, the two lesions had the characteristics of low grade astrocytoma, suggesting that the midbrain astrocytoma may have been disseminated via the cerebral spinal fluid to the infundibular recess. Postoperatively this patient received radiotherapy for nearly one month. Although patients with these tumors are not usually administered adjunctive therapy, radiation and, combined modality therapy, including surgery, radiotherapy, and chemotherapy, may be beneficial in patients with midbrain gliomas with dissemination.

Endoscopic third ventriculostomy for hydrocephalus due to tectal glioma

BACKGROUND

Tectal gliomas commonly present with hydrocephalus from obstruction of the aqueduct of Sylvius. The creation of a ventriculostomy in the floor of the third ventricle (ETV) has been previously reported to by-pass aqueduct obstruction. The goal of this study was to determine the safety and efficacy of ETV in the presence of an obstructing tectal glioma.

METHODS

We retrospectively reviewed the clinical presentation, management, and clinical outcome after ETV in patients diagnosed with tectal glioma and obstructive hydrocephalus in our institution over a period of 15 years. Shunt freedom at follow-up was the main outcome variable. Long-term clinical outcome was assessed at the most recent clinic visit. Clinical outcome was ranked as excellent, good, or poor according to resolution of symptoms and patient functional status.

RESULTS

The median age at presentation was 16.5 years (range: 6.4 to 59 years) and the most common presenting symptom was headache. Eleven patients had ETV as a primary procedure and three patients underwent ETV as a substitute for shunt revision at the time of shunt failure. At follow-up (median 3.9 years, range: 2.2 to 7 years) 13 of 14 patients remain shunt independent with excellent (n=9) or good outcomes (n=5).

CONCLUSIONS

In patients with tectal glioma causing obstructive hydrocephalus, ETV can be performed safely in the primary setting or as a substitute for shunt revision. A high rate of shunt freedom (78%-100%) at prolonged follow-up can be expected in this patient population.

Tectal Lesions in Children: A Long-Term Follow-Up Volumetric Tumor Growth Analysis in Surgical and Nonsurgical Cases

BACKGROUND/AIMS

Different tectal masses have been described; most are low-grade gliomas. Only 20-30% of all lesions grow, as shown on follow-up MRIs, requiring surgical resection at some point. The aim of this study is to describe the experience of a single institution managing pediatric patients with tectal lesions.

METHODS

We retrospectively studied and analyzed 40 children with tectal lesions managed from 1990 to 2006; the mean age at diagnosis was 9.4 years. A volumetric classification was used to analyze tumor growth trends. More than 1 year of imaging follow-up was available for 23 patients.

RESULTS AND CONCLUSION

Medium- and large-volume-size lesions were associated with the need for surgery. About half of the nonsurgical lesions grew at least 50% over a period of 4.5 years and did not require surgical resection.

The Impact of Endoscopic Third Ventriculostomy on Shunt Revision Rate: A 14-Year Experience at a Single Institution

BACKGROUND

Shunt-related procedures in the treatment of hydrocephalus are often associated with malfunction and revision resulting in significant patient morbidity and financial impact on the health care system. The increased utilization of endoscopic third ventriculostomy (ETV) as an alternative treatment paradigm for obstructive hydrocephalus carries the theoretical expectation of concomitant decreased numbers of shunt procedures. The objective of the present study was to determine the impact of ETV on shunt-related procedures within a 14-year interval (1998-2011), during which ETV has gained wider acceptance and greater utilization.

METHODS

This retrospective chart review describes the annual rate of pediatric patients who underwent either ETV or shunt-related procedures at New York Presbyterian Hospital Weill-Cornell Medical Center. Statistical analyses were done to analyze possible correlation between relative rates of these cases.

RESULTS

During the 14-year study period, 954 procedures were performed for the treatment of hydrocephalus (159 ETVs and 795 shunt-related procedures). Of the shunts, 356 were initial insertions and 439 were revisions. The number of ETVs increased from 8 procedures in 1998/1999 to 34 in 2010/2011, whereas the total number of annual shunt-related procedures decreased from 146 to 99. The relative ratios of ETVs and shunt-related procedures to the total number of cases demonstrate an inverse relationship over time (Spearman correlation coefficient rs = -1.0; P = 0.0004).

CONCLUSIONS

Based on prior cost-effectiveness analyses, the observed trend of the inverse correlation between ETVs and shunt-related procedures may contribute to financial savings and improvement in patient outcomes. Further study is required to define the impact on morbidity and associated success rates.

Long-term outcome in children with low grade tectal tumours and obstructive hydrocephalus

BACKGROUND

Neuropsychological deficits after treatment of paediatric brain tumour are well known, but not the role of hydrocephalus in these deficits.

AIMS

To study long-term neurological, cognitive, and behavioural deficits in children with a low grade tectal tumour and acquired obstructive hydrocephalus.

METHODS

In a consecutive series of 12 children with low-grade tectal tumour diagnosed in our hospital between 1994 and 2008, neurologic, neuropsychological, and radiologic data were prospectively collected. Intelligence, memory, attention, language, visual-spatial, and executive functions were assessed. Median follow-up was 2 years and 9 months.

RESULTS

At follow-up, most frequent neurologic disability was fatigue in children with a low-grade tectal tumour. They scored lower on sustained attention, long-term memory and had more behavioural problems. Factor influencing cognition was persisting severe hydrocephalus at time of assessment. The cognitive problems resulted in 60% of children needing assistances of special services at school.

CONCLUSIONS

At long-term, children with a low-grade tectal tumour display invalidating neuropsychological impairments resulting in educational problems. Adequate treatment of hydrocephalus may result in better cognitive functioning. Our findings suggest that part of the symptoms of the cerebellar cognitive affective syndrome may not have resulted from a cerebellar lesion itself but rather from a cerebral dysfunction or compression of supratentorial structures in the cerebello-cortical circuitry due to the obstructive hydrocephalus.

Indication for endoscopic third ventriculostomy

BACKGROUND

Endoscopic third ventriculostomy (ETV) is increasingly prevalent among pediatric neurosurgeons as the initial treatment for hydrocephalus. The combination of ETV and choroid plexus cauterization (ETV/CPC) has improved the success rate among infants with hydrocephalus for whom ETV alone is much less successful. In parts of the developing world where there are economic and human resource constraints, this mode of treatment may be more appropriate than the routine use of shunts, which are prone to failures that require urgent surgical treatment. Here we review indications for the use of ETV or ETV/CPC as the primary treatment for hydrocephalus.

CONCLUSION

Primary treatment of hydrocephalus by ETV can avoid shunt-dependence and its complications for many patients. Optimal results depend upon proper patient selection and the use of combined ETV/CPC when treating infants.

Endoscopy in the management of intra-ventricular lesions: preliminary experience in the Middle East

OBJECTIVES

The study is aimed at evaluating neuroendoscopic procedures in the management of various intra-cranial intra-ventricular lesions.

METHODS

We retrospectively review 24 consecutive patients harboring various intra-ventricular lesions with or without associated hydrocephalus, operated and managed by the authors between December 2002 and December 2007. Depending on the preoperative imaging and working diagnosis, endoscopic biopsy or endoscopic resection/debulking, along with concomitant treatment of hydrocephalus via third ventriculostomy or fenestration of the septum pellucidum and ventriculo-peritoneal shunting, were done.

RESULTS

The single endoscopic procedure was successful in most of the patients (22/24), where the goals of surgery in attaining a diagnostic biopsy or resection, and simultaneous treatment of hydrocephalus, were attained helping guide further therapy. The endoscopic procedure was the only procedure needed in most of the patients.

CONCLUSIONS

The endoscopic procedures carried a high success rate in the management of intra-ventricular lesions, and were especially valuable in patients harboring chemo and/or radiosensitive deep seated tumors.

Brainstem gliomas in children and adults

PURPOSE OF REVIEW

The purpose of this review is to determine if recent advances in diagnostic and treatment modalities result in improvement in the pattern of care of brainstem gliomas.

RECENT FINDINGS

New MRI techniques may contribute to differential diagnosis and aid neurosurgeons in removing resectable brainstem tumors. A better radiological analysis of these heterogeneous tumors improves their classification and helps to better distinguish prognosis subgroups. However, biopsy remains indicated in many contrast enhancing brainstem masses in adults because of the great variety of differential diagnosis.

SUMMARY

Diffuse brainstem glioma is the most common subtype of brainstem tumor and remains a devastating malignancy in children. Conventional radiotherapy is the standard of care and chemotherapy has been disappointing to date. Given the lack of efficacy of conventional drugs, a better understanding of the biology of this tumor is the key to more targeted therapy.