Cervicomedullary tumors in children

Single-agent Bevacizumab in the Treatment of Symptomatic Newly Diagnosed and Recurrent/Refractory Pediatric Cervicomedullary Brainstem Low-grade Gliomas: A Single Institutional Experience

Bevacizumab-based therapies have been utilized as single or combination therapy of refractory/recurrent pediatric low-grade gliomas. Its efficacy for symptomatic cervicomedullary low-grade gliomas (cmLGGs) in the upfront and the recurrent setting is less known. We report our retrospective single institutional experience from 2015 to 2021 with single-agent bevacizumab for symptomatic cmLGG. Six consecutive patients (4 female, ages 2 to 12 y) with newly diagnosed (n=3) and recurrent/refractory (n=3) symptomatic nondisseminated cmLGG (5/6 biopsy-proven, 2 BRAFV600E, 2 BRAF-KIAA1549) were treated with single-agent bevacizumab. All demonstrated radiographic response most pronounced on post-gadolinium T1-weighted magnetic resonance imaging (2 complete, 4 partial) at a median of 8 weeks (range: 2 to 12 wk). Clinical response was seen in all patients with improvement in cranial nerve abnormalities (3 recurrent/refractory, 1 newly diagnosed), strength (2 recurrent/refractory, 2 newly diagnosed), pain (2 recurrent/refractory), and anorexia (1 newly diagnosed). Four patients (2 recurrent/refractory, 2 newly diagnosed) experienced disease progression on subsequent adjunct therapies, 2 of which (the 2 newly diagnosed patients) are currently being rechallenged. At a mean follow-up of 7 months, all patients are clinically stable without disease progression. Single-agent bevacizumab may be effective in the management of symptomatic newly diagnosed and recurrent/refractory cmLGG and warrants further evaluation in a clinical trial setting.

Management and outcome of pediatric brainstem and cerebellar peduncular low-grade gliomas: a retrospective analysis of 62 cases

PURPOSE

This study was designed to present our experience and recommendations regarding the management of pediatric brainstem and peduncular low-grade gliomas (LGGs).

METHODS

Retrospective analysis was performed for pathologically proven brainstem or cerebellar peduncular LGGs in patients admitted between 2014 and 2019. These lesions were classified into the dorsal exophytic, focal brainstem, cervicomedullary, lower peduncular, and upper peduncular groups, and this classification was the basis for the surgical approach for the lesions.

RESULTS

Sixty-two pediatric patients were included, and their distribution among the aforementioned groups were as follows: 12, 12, 3, 16, and 19 cases in the dorsal exophytic, focal brainstem, cervicomedullary, upper peduncular, and lower peduncular groups, respectively. Stereotactic biopsy was performed for all cases in the focal brainstem group, whereas other groups underwent open excision. Gross total resection (GTR) was achieved in 20 cases (40%), near-total resection (NTR) was achieved in 17 cases (34%), and subtotal resection (STR) was achieved in 13 cases (26%). The extent of GTR and NTR for the upper peduncular, lower peduncular, dorsal exophytic, and cervicomedullary groups were 81.2%, 68.4%,75%, and 66.6%, respectively. Then, 32 cases received chemotherapy. The 3- and 5-year progression-free survival rates were 95% (95% confidence interval (CI) 89.5-100%) and 90.3% (95% CI 79.9-100%), respectively. A significant difference in the 3-year progression-free survival rate was observed between the GTR and NTR groups (p = 0.06; 100% vs. 88.2% (95% CI 72.9-100%)).

CONCLUSION

Surgery plays a definitive curative role in grossly resected cases. Additionally, the role of surgical debulking should be considered, even if GTR is impossible. Meanwhile, chemotherapy showed a beneficial role in patients with focal brainstem lesions and progressive lesions, those with STR, and some patients with NTR.

Cervicomedullary Gliomas in Pediatric Age: A Systematic Review of the Literature and Tertiary Care Center Experience

INTRODUCTION

Cervicomedullary gliomas (CMGs) are usually low-grade tumors often found in the pediatric age. Histological findings, treatments, and classification have been much the same for 40 years, although histological and molecular classifications have largely been developed for other pediatric CNS tumors. The management and treatment of pediatric CMG are still conducted by many authors according to their anatomical location and characteristics, independently from histology.

METHODS

We conducted a literature review in PubMed (Medline) to identify relevant contributions about pediatric CMG published until December 31, 2021. We also analyzed a series of 10 patients with CMG treated from 2006 to 2021 at IRCCS Istituto Nazionale dei Tumori. The aim of the present review was to see whether and how the diagnosis, treatment, and classification of CMGs in children have developed over time, especially in the context of molecular advancements, and to analyze our single-center experience in the last 15 years.

RESULTS

Thirty articles have been included in the review. Articles have been divided into two historical periods (1981-2000 and 2001-2021) and data from different series were analyzed to see how much the management and treatment of pediatric CMG have changed during years. Analysis of our series of 10 patients affected by CMG was also performed to compare it with the literature.

DISCUSSION

Management and classification of CMG in children have not dramatically changed during years. However, new insight from molecular diagnostics and target therapies and the development of radiological, neurophysiological, and radiotherapy techniques have updated treatment modalities in the last 20 years. Treatment modalities and their innovations have been reviewed and discussed. Further studies are needed to standardize and customize treatment protocols for these tumors.

High frequency of disease progression in pediatric spinal cord low-grade glioma (LGG): management strategies and results from the German LGG study group

BACKGROUND

Knowledge on management of pediatric spinal cord low-grade glioma (LGG) is scarce.

METHODS

We analyzed clinical datasets of 128 pediatric patients with spinal LGG followed within the prospective multicenter trials HIT-LGG 1996 (n = 36), SIOP-LGG 2004 (n = 56), and the subsequent LGG-Interim registry (n = 36).

RESULTS

Spinal LGG, predominantly pilocytic astrocytomas (76%), harbored KIAA1549-BRAF fusion in 14/35 patients (40%) and FGFR1-TACC1 fusion in 3/26 patients (12%), as well as BRAFV600E mutation in 2/66 patients (3%). 10-year overall survival (OS) and event-free survival (EFS) was 93% ± 2% and 38% ± 5%, respectively. Disseminated disease (n = 16) was associated with inferior OS and EFS, while age ≥11 years and total resection were favorable factors for EFS. We observed 117 patients following total (n = 24) or subtotal/partial resection (n = 74), biopsy (n = 16), or radiologic diagnosis only (n = 3). Eleven patients were treated first with chemotherapy (n = 9) or irradiation (n = 2). Up to 20.8 years after diagnosis/initial intervention, 73/128 patients experienced one (n = 43) or up to six (n = 30) radiological/clinical disease progressions. Tumor resections were repeated in 36 patients (range, 2-6) and 47 patients required nonsurgical treatment (chemotherapy, n = 20; radiotherapy, n = 10; multiple treatment lines, n = 17). Long-term disease control for a median of 6.5 (range, 0.02-20) years was achieved in 73/77 patients following one (n = 57) or repeated (n = 16) resections, and in 35/47 patients after nonsurgical treatment.

CONCLUSIONS

The majority of patients experienced disease progression, even after years. Multiple interventions were required for more than a third, yet multimodal treatment enabled long-term disease control. Molecular testing may reveal therapeutic targets.

Congenital Mobile Atlantoaxial Dislocation with Cervicomedullary Astrocytoma in Pediatric Patient

Congenital mobile atlantoaxial dislocation with cervicomedullary astrocytoma has never been described. We present a case of a 7-year-old male child who presented to us with gradually progressive spastic quadriparesis following a fall from table. His lateral radiograph and magnetic resonance images showed mobile atlantoaxial dislocation with intramedullary heterogeneously enhancing cervicomedullary mass. The patient underwent suboccipital craniectomy with C1-4 laminectomy. Tumor was pinkish grey, tenacious with ill-defined plane and cyst at poles. C1-C2 fusion was done using C1 lateral mass and C2 pars screw and rod system with onlay bone graft. Histopathology revealed pilocytic astrocytoma. At the time of discharge, the patient showed improvement in spasticity. Postoperative lateral radiograph showed reduced atlantoaxial dislocation with stable construct.

Outcome Features Analysis in Intramedullary Tumors of the Cervicomedullary Junction: A Surgical Series

OBJECT

 The aim of this study is to investigate the impact of surgery for different cervicomedullary lesions on symptomatic pattern expression and postoperative outcome. We focused on specific outcome features of the early and late postoperative assessments. The former relies on surgery-related transient and permanent morbidity and feasibility of radicality in eloquent areas, whereas the latter on long-term course in lower grade tumors and benign tumorlike lesions (cavernomas, etc.).

MATERIAL AND METHODS

 We retrospectively analyzed 28 cases of intramedullary tumors of the cervicomedullary junction surgically treated at our institution between 1990 and 2018. All cases were stratified for gender, histology, macroscopic appearance, location, surgical approach, and presence of a plane of dissection (POD). Mean follow-up was 5.6 years and it was performed via periodic magnetic resonance imaging (MRI) and functional assessments (Karnofsky Performance Scale [KPS] and modified McCormick [MC] grading system).

RESULTS

 In all, 78.5% were low-grade tumors (or benign lesions) and 21.5% were high-grade tumors. Sixty-one percent underwent median suboccipital approach, 18% a posterolateral approach, and 21% a posterior cervical approach. Gross total resection was achieved in 54% of cases, near-total resection (>90%) in 14%, and subtotal resection (50-90%) in 32% of cases. Early postoperative morbidity was 25%, but late functional evaluation in 79% of the patients showed KPS > 70 and MC grade I; only 21% of cases showed KPS < 70 and MC grades II and III at late follow-up. Mean overall survival was 7 years in low-grade tumors or cavernomas and 11.7 months in high-grade tumors. Progression-free survival at the end of follow-up was 71% (evaluated mainly on low-grade tumors).

CONCLUSIONS

 The surgical goal should be to achieve maximal cytoreduction and minimal postoperative neurologic damage. Functional outcome is influenced by the presence of a POD, radicality, histology, preoperative status, and employment of advanced neuroimaging planning and intraoperative monitoring.

Pediatric low grade focal brainstem glioma: outcomes of different treatment strategies and prognostic factors

Background: This study explores the prognostic factors and outcomes of different treatment modalities in focal brain stem glioma (FBSG). Materials & methods: Pediatric FBSG patients diagnosed during 2010-2017 were retrospectively reviewed for clinical and therapeutic data. Results: A total of 71 cases were identified and the median age was 6.4 years. The 5-year overall- and progression-free survival were 74.5 and 70.6%, respectively. Radiotherapy was the main line of treatment (66.2%) and there were no survival differences between radiotherapy, chemotherapy and surveillance groups. Two independent poor prognostic factors were identified on multivariate analysis: age <8 years and cervicomedullary tumor site (p = 0.02 for both). Conclusion: Surveillance, radiotherapy and chemotherapy have comparable clinical outcomes in pediatric FBSG.

Cervicomedullary Ependymoma with Hemorrhage: A Case Report and Review of Literature

Ependymoma is a rare tumor central nervous system that arises from the ependymal lining of the ventricles or the central canal of the spinal cord. They are of neuroectodermal in origin and constitute about 30%–86% of tumors arising in the spinal cord. The occurrence of these tumors in the cervicomedullary region is very rare. Sudden symptomatic neurologic presentations due to hemorrhage in cervicomedullary ependymoma is very rare and so far have never been reported. Mostly presenting as neurologic deficits involving limbs, these tumors pose a technical challenge in their removal. We present a patient who presented with sudden-onset dysesthesia of the upper and lower limbs. On imaging, he was found to have a cystic medullary tumor extending to the cervical region with hemorrhage. We discuss the epidemiology, surgical challenges, and outcome along with review of literature of these rare tumors located in this precarious location.

Pediatric ganglioglioma of the brainstem and cervicomedullary junction: a retrospective cohort study

OBJECTIVE

Ganglioglioma is a low-grade central nervous system neoplasm with a pediatric predominance, accounting for 10% of all brain tumors in children. Gangliogliomas of the cervicomedullary junction (GGCMJs) and brainstem (GGBSs) present a host of management challenges, including a significant risk of surgical morbidity. At present, understanding of the prognostic factors-including BRAF V600E status-is incomplete. Here, the authors report a single-institution GGCMJ and GGBS experience and review the pertinent literature.

METHODS

A prospectively maintained neurosurgical database at a large tertiary care academic referral center was retrospectively queried for cases of GGCMJ pathologically confirmed in the period from 1995 to 2015; appropriate cases were defined by diagnosis codes and keywords. Secondary supplemental chart review was conducted to confirm or capture relevant data. The primary study outcome was treatment failure as defined by evidence of radiographic recurrence or progression and/or clinical or functional decline. A review of the literature was conducted as well.

RESULTS

Five neurosurgically managed GGBS patients were identified, and the neoplasms in 4 were classified as GGCMJ. All 5 patients were younger than 18 years old (median 15 years, range 4-16 years) and 3 (60%) were female. One patient underwent gross-total resection, 2 underwent aggressive subtotal resection (STR), and 2 underwent stereotactic biopsy only. All patients who had undergone STR or biopsy required repeat resection for tumor control or progression. Progressive disease was treated with radiotherapy in 2 patients, chemotherapy in 2, and chemoradiotherapy alone in 1. Immunostaining for BRAF V600E was positive in 3 patients (60%). All 5 patients experienced at least one major complication, including wound infection, foot drop, hemiparesis, quadriparesis, cranial neuropathy, C2-3 subluxation, syringomyelia, hydrocephalus, aspiration, and coma. Overall mortality was 20%, with 1 death observed over 11 years of follow-up.

CONCLUSIONS

GGBS and GGCMJ are rare, benign posterior fossa tumors that carry significant perioperative morbidity. Contemporary management strategies are heterogeneous and include combinations of resection, radiotherapy, and chemotherapy. The BRAF V600E mutation is frequently observed in GGBS and GGCMJ and appears to have both prognostic and therapeutic significance with targeted biological agents.

Evaluating pediatric spinal low-grade gliomas: a 30-year retrospective analysis

PURPOSE

Most pediatric spinal tumors are low-grade gliomas (LGGs). Characterization of these tumors has been difficult given their heterogeneity and rare incidence. The objective was to characterize such tumors diagnosed at our institution.

METHODS

Spinal tumors diagnosed in our pediatric patients between 1984 and 2014 were reviewed retrospectively. Demographics, presentation, pathology, imaging, management, and sequelae were examined.

RESULTS

Forty patients had spinal LGG tumors, 24 (62%) of which were pilocytic astrocytomas. The most common initial presentations were pain (n = 15), partial extremity paralysis (n = 13), and ataxia (n = 11), with the diagnosis frequently delayed by months (median = 5.9 months, range 4 days-6.2 years). Twenty-nine patients had some tumor resection, and 8 required adjuvant therapy with chemotherapy (n = 4) or radiation (n = 4) post-resection. Ten other patients received only biopsy for histologic diagnosis, who were treated with chemotherapy (n = 4) or radiation (n = 5) post biopsy. Tumor progression was noted in 16 patients (2 after gross-total resection; 10, partial resection; and 4, biopsy). During the evaluation period, 3 patients died secondary to tumor progression. BRAF status could have shortened progression-free survival: patients with BRAFV600E mutations (n = 3) all experienced progression within 10 months. Long-term sequelae of the disease/treatment were mostly residual neurologic deficits (paresthesia, paralysis), chemotherapy-induced hearing loss, and scoliosis.

CONCLUSIONS

Spinal LGG is a rare entity with significant long-term effects. Although surgery is the most common initial treatment option, more in-depth analysis of molecular biomarkers may improve stratification and prognostication.

Microsurgical resection of brainstem cervicomedullary ganglioglioma: operative video and technique of creating a surgical pseudoplane for near-total resection

Cervicomedullary gangliogliomas are rare low-grade neoplasms of the brainstem. They can be challenging lesions to resect due to the eloquent location in the brainstem. In some instances, the absence of a clear surgical plane between the tumor and normal neural tissue can prohibit a complete resection. Therefore, it is important to leave a thin rim of residual tumor at the tumor-brainstem interface in order to avoid irreversible neurological injury. In this operative video, the authors demonstrate the technique to develop a surgical pseudoplane using sharp microdissection for a cervicomedullary brainstem ganglioglioma without a clear interface between the tumor and normal neural tissue. This strategy allowed for radical near-total resection of the tumor, thereby maximizing the extent of removal while preserving neurological function. Postoperatively, the patient had normal neurological function and returned to work without any disability. In summary, due to the lack of a clear surgical dissection plane, a pseudoplane near the surgical interface can be performed using sharp dissection to facilitate radical near-total resection.

The video can be found here: https://youtu.be/biD4G1Hh0yk.

Enhancing nodular lesions in Chiari II malformations in the setting of persistent hindbrain herniation: case report and literature review

BACKGROUND

Chiari II malformation includes concomitant cerebellar tonsillar herniation, hydrocephalus, and myelomeningocele. Rarely, pediatric patients with persistent hindbrain herniation develop a new enhancing nodule at the cervicomedullary junction as adults. These new lesions may be suspicious for neoplastic growth, but it remains unclear if neurosurgical intervention is necessary.

CASE REPORT

A 27-year-old female patient with history of Chiari II malformation and persistent hindbrain herniation presented with a 3-month history of headache and upper extremity weakness and numbness. Neuroimaging revealed a new enhancing nodule near the cervicomedullary junction suspicious for neoplasm. Following posterior fossa decompression and excision of the enhancing lesion, pathological analysis demonstrated only benign glioneural heterotopia.

RESULTS

New enhancing nodules at the cervicomedullary junction in Chiari II malformation are exceedingly rare and are likely benign, reactive changes rather than a neoplastic process. Biopsy or surgical excision of these lesions is likely unnecessary for asymptomatic patients.

Combined Use of Diffusion Tractography and Advanced Intraoperative Imaging for Resection of Cervical Intramedullary Spinal Cord Neoplasms: A Case Series and Technical Note

BACKGROUND

Intramedullary spinal cord neoplasms (ISCN) pose significant management challenges. Advances in magnetic resonance imaging (MRI) (such as diffusion tensor imaging, DTI) have been utilized to determine the infiltrative nature and resectability of ISCN. However, this has not been applied to intraoperative decision making.

OBJECTIVE

To present a case series of 2 patients with ISCN, the first to combine use of DTI, pre- and intraoperative 3-dimensional (3D) virtual reality imaging, and microscope integrated navigation with heads-up display.

METHODS

Two patients who underwent surgery for ISCN were included. DTI images were obtained and 3D images were created using Surgical Theater (Surgical Theater SRP, Version 7.4.0, Cleveland, Ohio). Fiducials were used to achieve accurate surface registration to C4. Navigation confirmed the levels of laminectomy necessary. The microscope was integrated with Brainlab (Brainlab AG Version 3.0.5, Feldkirchen, Germany) and the tumor projected in the heads-up display. Surgical Theater was integrated with Brainlab to allow for real time evaluation of the 3D tractography.

RESULTS

Case 1: All tracts were pushed away from the tumor, suggesting it was not infiltrative. Surgical Theater and Brainlab assisted in confirming midline despite the abnormal swelling of the cord so the myelotomy could be performed. The heads-up display outline demonstrated excellent correlation to the tumor. Gross total resection was achieved. Diagnosis of ependymoma was confirmed. Case 2: Some tracts were going through the tumor itself, suggesting an infiltrative process. Surgical Theater and Brainlab again allowed for confirmation of the midline raphe. Near total resection of the enhancing portion was achieved. Diagnosis of glioblastoma was confirmed.

CONCLUSION

This is a proof of concept application where multi-modal imaging technology was utilized for safest maximal ISCN resection.

Surgical outcomes of pediatric spinal cord astrocytomas: systematic review and meta-analysis

OBJECTIVE

Pediatric spinal astrocytomas are rare spinal lesions that pose unique management challenges. Therapeutic options include gross-total resection (GTR), subtotal resection (STR), and adjuvant chemotherapy or radiation therapy. With no randomized controlled trials, the optimal management approach for children with spinal astrocytomas remains unclear. The aim of this study was to conduct a systematic review and meta-analysis on pediatric spinal astrocytomas.

METHODS

The authors performed a systematic review of the PubMed/MEDLINE electronic database to investigate the impact of histological grade and extent of resection on overall survival among patients with spinal cord astrocytomas. They retained publications in which the majority of reported cases included astrocytoma histology.

RESULTS

Twenty-nine previously published studies met the eligibility criteria, totaling 578 patients with spinal cord astrocytomas. The spinal level of intramedullary spinal cord tumors was predominantly cervical (53.8%), followed by thoracic (40.8%). Overall, resection was more common than biopsy, and GTR was slightly more commonly achieved than STR (39.7% vs 37.0%). The reported rates of GTR and STR rose markedly from 1984 to 2015. Patients with high-grade astrocytomas had markedly worse 5-year overall survival than patients with low-grade tumors. Patients receiving GTR may have better 5-year overall survival than those receiving STR.

CONCLUSIONS

The authors describe trends in the management of pediatric spinal cord astrocytomas and suggest a benefit of GTR over STR for 5-year overall survival.

Pediatric Cerebellar Tumors: Emerging Imaging Techniques and Advances in Understanding of Genetic Features

Cerebellar tumors are the most common group of solid tumors in children. MR imaging provides an important role in characterization of these lesions, surgical planning, and postsurgical surveillance. Preoperative imaging can help predict the histologic subtype of tumors, which can provide guidance for surgical planning. Beyond histology, pediatric brain tumors are undergoing new classification schemes based on genetic features. Intraoperative MR imaging has emerged as an important tool in the surgical management of pediatric brain tumors. Effective understanding of the imaging features of pediatric cerebellar tumors can benefit communication with neurosurgeons and neuro-oncologists and can improve patient management.

Pediatric Cerebellar Tumors: Emerging Imaging Techniques and Advances in Understanding of Genetic Features

Cerebellar tumors are the most common group of solid tumors in children. MR imaging provides an important role in characterization of these lesions, surgical planning, and postsurgical surveillance. Preoperative imaging can help predict the histologic subtype of tumors, which can provide guidance for surgical planning. Beyond histology, pediatric brain tumors are undergoing new classification schemes based on genetic features. Intraoperative MR imaging has emerged as an important tool in the surgical management of pediatric brain tumors. Effective understanding of the imaging features of pediatric cerebellar tumors can benefit communication with neurosurgeons and neuro-oncologists and can improve patient management.