Surgical considerations of spinal ependymomas in the pediatric population

Current management in the treatment of intramedullary ependymomas in children

PURPOSE

Current management of pediatric intramedullary ependymoma is extrapolated from adult series since large studies in children are unavailable. This has led us to share our experience with this rare tumor and compare it to the literature and to review and highlight important aspects of current management and point out inconsistencies.

METHODS

This is a retrospective analysis of patients with intramedullary ependymoma managed at our institution between 2004 and 2021.

RESULTS

During the study period, 5 patients were treated for intramedullary ependymoma. Cases of myxopapillary ependymoma were excluded. The mean age of our cohort was 11.2 years. We identified 4 cases of grade II ependymoma and 1 case of grade III ependymoma. Gross tumor removal (GTR) was achieved in two patients (40%) of patients. One patient was treated with radiotherapy for recurrence and two patients received chemotherapy. There were no cases of recurrence among patients treated with GTR, but in all patients treated with STR. Eighty percent of patients either improved or stayed stable neurologically. During follow-up (mean 73 months), 2 patients died of disease.

CONCLUSION

GTR and tumor grade remain the key prognostic factor of long-term tumor-free survival. Many questions prevail regarding outcomes, correct use of adjuvant therapy, and prognostic factors.

Bicentric Treatment Outcomes After Proton Therapy for Nonmyxopapillary High-Grade Spinal Cord Ependymoma in Children

PURPOSE

Few studies report outcomes in children treated with radiation for nonmyxopapillary ependymoma of the spinal cord, and little evidence exists to inform decisions regarding target volume and prescription dose. Moreover, virtually no mature outcome data exist on proton therapy for this tumor. We describe our combined institutional experience treating pediatric classical/anaplastic ependymoma of the spinal cord with proton therapy.

METHODS AND MATERIALS

Between 2008 and 2019, 14 pediatric patients with nonmetastatic nonmyxopapillary grade II (n = 6) and grade III (n = 8) spinal ependymoma received proton therapy. The median age at radiation was 14 years (range, 1.5-18 years). Five tumors arose within the cervical cord, 3 within the thoracic cord, and 6 within the lumbosacral cord. Before radiation therapy, 3 patients underwent subtotal resection, and 11 underwent gross-total or near total resection. Two patients received chemotherapy. For radiation, the clinical target volume received 50.4 Gy (n = 8), 52.2 (n = 1), or 54 Gy (n = 5), with the latter receiving a boost to the gross tumor volume after the initial 50.4 Gy, modified to respect spinal cord tolerance.

RESULTS

With a median follow-up of 6.3 years (range, 1.5-14.8 years), no tumors progressed. Although most patients experienced neurologic sequela after surgery, only 1 developed additional neurologic deficits after radiation: An 18-year-old male who received 54 Gy after gross total resection of a lumbosacral tumor developed grade 2 erectile dysfunction. There were 2 cases of musculoskeletal toxicity attributable to surgery and radiation. At analysis, no patient had developed cardiac, pulmonary, or other visceral organ complications or a second malignancy.

CONCLUSION

Radiation to a total dose of 50 to 54 Gy can be safely delivered and plays a beneficial role in the multidisciplinary management of children with nonmyxopapillary spinal cord ependymoma. Proton therapy may reduce late radiation effects and is not associated with unexpected spinal cord toxicity.

Contemporary management of pediatric spinal tumors: a single institute's experience in Taiwan in the modern era

INTRODUCTION

Pediatric spinal tumors are unique pathologies treated by pediatric neurosurgeons. Special attention is required for the preservation of neural function and bony alignment. We reported our experience in the management of these challenging lesions.

METHODS

A total of 75 pediatric patients with spinal tumors treated at the National Taiwan University Hospital from 1998 to 2018 were identified retrospectively. Clinical data, radiographic image, and pathological report were reviewed for analysis.

RESULTS

There were 37 females and 38 males. The median age was 9 years. Thirty-eight tumors (50.6%) were extradural, 20 (26.7%) intradural extramedullary, and 17 (22.6%) intramedullary. The most common pathologies were glioma, ependymoma, and neuroblastoma. The rate of total and subtotal resection was 45.3% and 21.3%. Thirty-four patients (45.3%) required post-operative adjuvant therapy. Eight patients (10.6%) with spinal deformity had simultaneous tumor excision and spinal fusion surgery. Additional six (8%) patients had subsequent spinal fixation and fusion for deformity after primary tumor operation. Eighty-four percent of patients were ambulatory 3 years after operation. For patients with intradural extramedullary and intramedullary tumors, worse survival outcome was associated with tumor derived from CSF seeding and cranial involvement of spinal tumor, while poorer functional outcome was correlated with cranial involvement and adjuvant therapy with chemotherapy or radiotherapy.

CONCLUSIONS

Pediatric spinal tumor surgery carries low surgical morbidity and mortality under current standard of neurosurgical practice. Post-operative adjuvant therapy is required for nearly half of the cases. Spinal deformity requires special attention and sometimes surgical correction. Contemporary management of pediatric spinal tumors enables effective ablation of the lesion and delivers favorable outcome for the majority of patients.

Spinal cord tumors in children: A review of 21 cases treated at the same institution

INTRODUCTION

Spinal cord tumors in children (SCTC) are rare with a frequent diagnostic delay. Its management is multidisciplinary and challenging due to functional implications. The position of surgery is now better established but the role and timing of chemotherapy (CT) and radiotherapy (RT) still remains under debate. Adverse effects of treatments are important to be taken into account, in the follow-up of these children. The aim of this paper was to present a series of 21 cases of SCTC treated at the same institution, to briefly present clinical features, treatments and outcome, with a special focus on spinal deformities in children with this condition.

MATERIAL AND METHODS

Twenty-one consecutive SCTC were referred to our institution from 1990 to 2014. Data regarding age, sex, diagnostic delay, clinical examination, MRI, surgery, pathology, other treatment (CT and RT), orthopedic issues and follow-up of these children were retrospectively recorded.

RESULTS

Mean age was 8years (standard deviation: 5.2years) (range: 4 months-17years). Mean diagnosis delay was 5.5 months (standard deviation: 6.5 months) (range: 0 days-18 months). All children (10 girls, 11 boys) were operated on (10 partial removals, 7 subtotal and 4 gross total removals) as first-line treatment. Pathological results showed 12 juvenile pilocytic astrocytomas, 1 grade III astrocytoma, 1 grade IV astrocytoma, 3 oligodendrogliomas, 2 ependymomas, 1 glioblastoma and 1 rhabdoid tumor. Fourteen children (66.7%) received additional treatment: 12 CT and 7 RT. Ten children had postoperative spinal deformities. Mean follow-up (FU) was 71 months (5 months-180 months), with a median FU at 60 months, where 8 tumor progressions and 4 deaths were observed. Overall, survival (at 5years) was 81% and progression free survival (at 5years) was 67%.

CONCLUSION

Surgery is the goal standard for SCTC and the only appropriate treatment in cases of a low-grade lesion with stable disease on MR follow-up. Additional treatment must be reserved for high-grade lesions or tumor progression not attainable by a second look surgery. Spinal deformities are a frequent complication. Overall, survival and event free survival primarily depends on the pathology. Studies involving more centers are obligatory with the aim of collecting more cases and drawing more definitive conclusions regarding the management of these tumors.

Spinal tumors in children: long-term retrospective evaluation of a series of 134 cases treated in a single unit of pediatric neurosurgery

BACKGROUND CONTEXT

Spinal tumors in childhood are rare and heterogeneous, and their treatment is very demanding. It is necessary to both manage the disease and preserve the spinal stability so that the spine can grow normally. As a consequence, results in terms of both mortality and morbidity are often suboptimal.

PURPOSE

The results of a single pediatric neurosurgery institution are reported to highlight the peculiarities and pitfalls of the management of this disease. Tumors are analyzed from the point of view of their localization, histology, and outcome in terms of mortality and morbidity, with a special focus on postoperative spinal deformity.

STUDY DESIGN

The study design was retrospective.

PATIENT SAMPLE

Between 1995 and 2011, 134 children (75 males and 59 females) were admitted for spinal tumors, accounting for 7.7% of all the patients admitted for central nervous system malignancies. The mean age was 8.5 years (14 days-26 years), and the mean follow-up was 28 months (3 months-13 years).

OUTCOME MEASURES

Clinical and radiological outcomes were evaluated to assess mortality, morbidity, and surgical outcomes. A special interest was directed toward morbidity related to spinal deformity and neurologic deficits.

METHODS

Patients were divided into four groups: intramedullary (46 patients), intradural extramedullary (25 patients), extradural (53 patients), and paravertebral tumors (10 patients). Data were obtained retrospectively from medical records and radiological archives.

RESULTS

Low-grade glioma was the most common histology (14.1%). One hundred seventeen patients were surgically treated, with a total of 138 surgical procedures. A posterior approach was chosen in 111 cases, with osteoplastic laminotomy in 80. Radiotherapy was administered to 22 patients and chemotherapy to 26. At the last follow-up, 16 patients (11.9%) had died. A good control of the tumor with clinical improvement was reported in 100 patients (74.6%). Five patients developed a spinal instability (3.7%).

CONCLUSIONS

The goals of surgery should be histology, spine and nerve root decompression, and preservation of spinal stability. In our experience, osteoplastic laminotomy was a good surgical approach to perform the resection of the tumor with a low risk of secondary spinal instability.

Intraoperative changes in transcranial motor evoked potentials and somatosensory evoked potentials predicting outcome in children with intramedullary spinal cord tumors

OBJECT

Intraoperative dorsal column mapping, transcranial motor evoked potentials (TcMEPs), and somatosensory evoked potentials (SSEPs) have been used in adults to assist with the resection of intramedullary spinal cord tumors (IMSCTs) and to predict postoperative motor deficits. The authors sought to determine whether changes in MEP and SSEP waveforms would similarly predict postoperative motor deficits in children.

METHODS

The authors reviewed charts and intraoperative records for children who had undergone resection for IMSCTs as well as dorsal column mapping and TcMEP and SSEP monitoring. Motor evoked potential data were supplemented with electromyography data obtained using a Kartush microstimulator (Medtronic Inc.). Motor strength was graded using the Medical Research Council (MRC) scale during the preoperative, immediate postoperative, and follow-up periods. Reductions in SSEPs were documented after mechanical traction, in response to maneuvers with the cavitational ultrasonic surgical aspirator (CUSA), or both.

RESULTS

Data from 12 patients were analyzed. Three lesions were encountered in the cervical and 7 in the thoracic spinal cord. Two patients had lesions of the cervicomedullary junction and upper spinal cord. Intraoperative MEP changes were noted in half of the patients. In these cases, normal polyphasic signals converted to biphasic signals, and these changes correlated with a loss of 1-2 grades in motor strength. One patient lost MEP signals completely and recovered strength to MRC Grade 4/5. The 2 patients with high cervical lesions showed neither intraoperative MEP changes nor motor deficits postoperatively. Dorsal columns were mapped in 7 patients, and the midline was determined accurately in all 7. Somatosensory evoked potentials were decreased in 7 patients. Two patients each had 2 SSEP decreases in response to traction intraoperatively but had no new sensory findings postoperatively. Another 2 patients had 3 traction-related SSEP decreases intraoperatively, and both had new postoperative sensory deficits that resolved. One additional patient had a CUSA-related SSEP decrease intraoperatively, which resolved postoperatively, and the last patient had 3 traction-related sensory deficits and a CUSA-related sensory deficit postoperatively, none of which resolved.

CONCLUSIONS

Intraoperative TcMEPs and SSEPs can predict the degree of postoperative motor deficit in pediatric patients undergoing IMSCT resection. This technique, combined with dorsal column mapping, is particularly useful in resecting lesions of the upper cervical cord, which are generally considered to be high risk in this population. Furthermore, the spinal cord appears to be less tolerant of repeated intraoperative SSEP decreases, with 3 successive insults most likely to yield postoperative sensory deficits. Changes in TcMEPs and SSEP waveforms can signal the need to guard against excessive manipulation thereby increasing the safety of tumor resection.

Minimally invasive thoracic decompression for multi-level thoracic pathologies

We describe our experience using a minimal access approach for multi-level dorsal decompression of the thoracic spine that may limit approach-related soft-tissue injury and spinal destabilization. Additionally, three patients, each with unique compressive thoracic pathology, are discussed. A single minimal access technique, using multi-level hemilaminotomies, was used to address these unique pathologies via a similar approach. The three patients in this study had a mean age of 49.3 years (range: 45-55 years), mean estimated blood loss of 750 cc (range: 350-1000 cc), mean operative time of 3.8 hours (range: 3-5 hours), and a mean post-operative hospital stay of 2.3 days (range: 2-3 days). Complete decompression was achieved with resolution of symptoms in all patients. Long-term follow-up averaged 26.7 months (range: 15-36 months). Radiographic decompression was demonstrated in all patients. Minimal access techniques using muscle-splitting tubular retractor systems can effectively treat multi-level dorsal compression of the thoracic cord, while potentially limiting morbidity and long-term spinal instability.

Intramedullary medullocervical ependymoma--surgical treatment, functional recovery, and long-term outcome

To evaluate the long-term outcome and functional recovery of intramedullary medullocervical ependymoma (IME), the clinical charts of 38 surgically treated consecutive cases of IME were reviewed. Follow-up was obtained prospectively. The mean age of the patients (19 male and 19 female) was 35.3 years (range: 11-60 years). Complete resection was achieved in 33 (86.8%) patients. Fourteen patients worsened postoperatively; five and seven of these improved to their baseline levels within 1 and 3 months, respectively. By 1 year postoperatively, 17 patients returned to work. After a mean follow-up duration of 81.5 months, 31 patients improved or stabilized, and 3 had recurrence. The means of the modified McCormick grade (mMG) scores before the operation, at discharge, 1 year after the operation, and at the most recent evaluation were 1.76, 2.13, 1.82, and 1.84, respectively. A favorable long-term outcome of the mMG was associated with a good preoperative status (mMG I) (odds ratio [OR] = 9.956, p = 0.008) and well-defined tumor boundary (OR = 7.829, p = 0.035). Improvements in the postoperative walking dysfunction and paresthesia over time were associated with the absence of preoperative walking dysfunction (p = 0.047) and paresthesia (p = 0.028), respectively. The 12-year progression/recurrence-free survival and overall survival rates were 92.0% and 93.7%, respectively. The study suggests that the goal of surgery is to stabilize the preoperative neurological function and that a favorable outcome may be achieved in patients with good preoperative statuses and well-defined tumor boundaries. Surgery should be performed as soon as possible after the diagnoses and before the neurological functions deteriorate.

Complications associated with the treatment for spinal ependymomas

Spinal cord ependymomas are rare neoplasms, comprising approximately 5% of all CNS tumors and 15% of all spinal cord tumors. Although surgery was once reserved for diagnosis alone, the evolution of surgical practices has elevated resection to the treatment of choice for these lesions. While technological advances continue to improve the capacity for gross-total resections and thus decrease the risk of recurrence, ependymoma spinal surgery still contains a variety of potential complications. The presence of neurological deficits and deterioration are not uncommonly associated with spinal cord ependymoma surgery, including sensory loss, dorsal column dysfunction, dysesthetic syndrome, and bowel and bladder dysfunction, particularly in the immediate postoperative period. Surgical treatment may also lead to wound complications and CSF leaks, with increased risk when radiotherapy has been involved. Radiation therapy may also predispose patients to radiation myelopathy and ultimately result in neurological damage. Additionally, resections of spinal ependymomas have been associated with postoperative spinal instability and deformities, particularly in the pediatric population. Despite the advances in microsurgical techniques and intraoperative cord monitoring modalities, there remain a number of serious complications related to the treatment of spinal ependymoma tumors. Identification and acknowledgment of these potential problems may assist in their prevention, early detection, and increased quality of life for patients afflicted with this disease.

Symptomatic apoplexy in intramedullary ependymoma: a report of a pediatric patient

Spinal intramedullary ependymomas often harbor clinically asymptomatic intratumoral bleeds. Such tumors presenting with apoplectic events have not been described in the literature. The authors report on a 2-year-old female who presented with sudden loss of sensorimotor functions below the thoracic spine as a consequence of hemorrhage within an intramedullary ependymoma. The clinical, radiological, and surgical findings are described. Gross total resection provided near-normal spinal functions in the present case.