Myxopapillary ependymoma with intracranial metastases

Resection of disseminated recurrent myxopapillary ependymoma with more than 4-year follow-up: operative nuance for prolonged prone position. Illustrative case

BACKGROUND

Symptomatic disseminated myxopapillary ependymoma (MPE) in a young person presents a daunting challenge because the risks of prolonged prone positioning and spinal cord injury may outweigh the likelihood of attaining the benefit of gross total resection.

OBSERVATIONS

The authors reported the case of a 15-year-old girl with five discrete recurrent spinal cord ependymomas. The patient received a 25-hour surgical procedure for gross total resection of the tumors and fusion over an approximately 33-hour period. She experienced complete resolution of all preoperative neurological symptoms and subsequently received adjuvant radiation therapy. At 52 months after surgery, she was still experiencing neurologically intact, progression-free survival. This case illustrated one of the most extensive recurrent tumor resections for MPE with prolonged disease-free survival reported to date. It may also represent the longest prone position spinal case reported and was notable for a lack of any of the complications commonly associated with the prolonged prone position.

LESSONS

The authors discussed the complexity of surgical decision-making in a symptomatic patient with multiple disseminated metastases, technical considerations for resection of intradural and intramedullary spinal cord tumors, and considerations for avoiding complications during prolonged positioning necessary for spinal surgery.

Anaplastic myxopapillary ependymoma: A case report and review of literature

BACKGROUND

Myxopapillary ependymoma (MPE) is a pathological grade I tumor that arises in the filum terminale. MPE with anaplastic features is extremely rare, and only 5 cases have shown malignancy at the time of recurrence.

CASE SUMMARY

The patient (a 46-year-old woman) had undergone a MPE operation 30 years ago. After subtotal resection of the tumor located in L4-S1, it had a solid component that extended to the adjacent subcutaneous region. Histologically, the tumor consisted of a typical MPE with anaplastic features. The anaplastic areas of the tumor showed hypercellularity, a rapid mitotic rate, vascular proliferation, and connective tissue proliferation. Pleomorphic cells and atypical mitotic figures were occasionally observed. The MIB-1 index in this area was 12.3%. The immunohistochemical study showed immunoreactivity for vimentin, glial fibrillary acidic protein and S100. The morphological pattern and immunohistochemical profile were consistent with anaplastic MPE. The patient tolerated surgery well without new neurological deficits. She underwent local irradiation for the residual tumor and rehabilitation.

CONCLUSION

Although extremely rare, anaplastic MPE occurs in both pediatric and adult patients, similar to other ependymomas. At a minimum, close monitoring is recommended, given concerns about aggressive biological potential. In the future, further study is needed to determine the WHO classification criteria and genetic indicators of tumor progression. The possibility of malignant transformation of MPE should be taken into account, and patients with MPE should be treated with care and follow-up.

Spinal Intradural Extramedullary Ependymoma with Intracranial Metastasis and Leptomeningeal Spread: A Case Report and Comprehensive Review of Literature

Dorsolumbar intradural extramedullary ependymoma is a rare entity. Spinal metastases in patients with intracranial ependymoma are well described, but it is extremely rare for a spinal ependymoma to metastasize to brain. We describe a case of aggressive dorsolumbar intradural extramedullary ependymoma mimicking arachnoid cyst radiologically, which developed intracranial metastasis.

Occipital Intraparenchymal Myxopapillary Ependymoma: Case Report and Literature Review

Myxopapillary ependymoma (MPE) is a histological variant of ependymoma found in the conus medullaris or filum terminale region. Intracranial occurrence of the tumor is a rarity. The most characteristic histological feature of myxopapillary tumors is the abundance of intercellular and perivascular mucin and the arborizing vasculature, which tends to form papillae. We are reporting a 14-year-old patient presented with seizures caused by the right occipital region intraparenchymal lesion. Histopathology confirmed it to be MPE. Lesion was excised completely. Literature reviews on the topic are discussed regarding the histological findings, natural history, and outcome of surgically treated MPE. This is the fifth reported case of cerebral intraparenchymal primary MPE.

Myxopapillary ependymomas in children: imaging, treatment and outcomes

Myxopapillary ependymomas (MPEs) are rare spinal tumors in children. The natural history and clinical course of pediatric MPEs are largely unknown and the indication for adjuvant therapy remains to be clarified. We performed an IRB-approved, retrospective review of children with MPEs treated at the Dana-Farber/Boston Children's Cancer and Blood Disorder Center between 1982 and 2013. Eighteen children (age range 8-21 years, median age 14 years) met inclusion criteria. We reviewed the histopathology, magnetic resonance imaging, tumor location and stage, surgical management, adjuvant therapy, and clinical outcomes. The median follow-up duration was 9.4 years (range 1-30 years). Children most commonly presented with pain, scoliosis, and urinary symptoms. All primary tumors were located in the lower thoracic or lumbar spine. Nine children (50%) had leptomeningeal tumor seeding at presentation, most commonly located within the distal thecal sac. A gross-total resection was achieved in nine children (50%). Three children were treated with irradiation following initial surgery. No child received adjuvant chemotherapy at diagnosis. The 10-year event-free survival (EFS) was 26% ± 14.8. Children with disseminated disease trended towards inferior EFS compared to those with localized disease (10-year EFS 12.7% ± 12 vs. 57 ± 25%, p value 0.07). The 10-year overall survival was 100%. The efficacy of adjuvant irradiation could not be assessed due to the small sample size. Although children with MPEs frequently present with disseminated tumor and/or develop recurrent or progressive disease, their overall survival is excellent. Treatment should aim to minimize both tumor- and therapy-related morbidity.

Spinal Myxopapillary Ependymomas Demonstrate a Warburg Phenotype

PURPOSE

Myxopapillary ependymoma (MPE) is a distinct histologic variant of ependymoma arising commonly in the spinal cord. Despite an overall favorable prognosis, distant metastases, subarachnoid dissemination, and late recurrences have been reported. Currently, the only effective treatment for MPE is gross-total resection. We characterized the genomic and transcriptional landscape of spinal ependymomas in an effort to delineate the genetic basis of this disease and identify new leads for therapy.

EXPERIMENTAL DESIGN

Gene expression profiling was performed on 35 spinal ependymomas, and copy number profiling was done on an overlapping cohort of 46 spinal ependymomas. Functional validation experiments were performed on tumor lysates consisting of assays measuring pyruvate kinase M activity (PKM), hexokinase activity (HK), and lactate production.

RESULTS

At a gene expression level, we demonstrate that spinal grade II and MPE are molecularly and biologically distinct. These are supported by specific copy number alterations occurring in each histologic variant. Pathway analysis revealed that MPE are characterized by increased cellular metabolism, associated with upregulation of HIF1α. These findings were validated by Western blot analysis demonstrating increased protein expression of HIF1α, HK2, PDK1, and phosphorylation of PDHE1A. Functional assays were performed on MPE lysates, which demonstrated decreased PKM activity, increased HK activity, and elevated lactate production.

CONCLUSIONS

Our findings suggest that MPE may be driven by a Warburg metabolic phenotype. The key enzymes promoting the Warburg phenotype: HK2, PKM2, and PDK are targetable by small-molecule inhibitors/activators, and should be considered for evaluation in future clinical trials for MPE.

Outcome predictors in the management of spinal myxopapillary ependymoma: an integrative survival analysis

OBJECTIVES

The results in earlier studies have described a variable association with age, extent of resection, and radiotherapy (RT) correlating with the survival of myxopapillary ependymomas. The aim of our study is to perform a survival analysis on patient data gathered from a comprehensive review of the literature and determine the influence of these factors on progression-free (PFS) and overall survival (OS).

METHODS

A PubMed search was performed to select the articles containing information about the critical events (recurrence/death), time to events, and treatment characteristics (extent of resection with or without RT) in the patients with spinal myxopapillary ependymomas.

RESULTS

A total of 337 patients with information regarding the critical events, time to events, and treatment characteristics was selected for the inclusion. Patients in gross-total resection group had better PFS and OS (P = 0.001, P = 0.000 respectively). The patients in older age group (>35 years) had better PFS (P = 0.008). Overall PFS did not improve if RT was combined with surgery compared with surgery alone; however, the adjuvant RT benefitted the patients age ≤35 years. RT dose >50 Gy had significant influence on the PFS (P = 0.034).

CONCLUSION

Gross-total resection plays the most important role in improving PFS and OS. Older patients had better PFS; however, the influence of adjuvant RT was significant in younger age groups. A dose of >50 Gy improves the results, but a randomized controlled study is warranted to arrive at a definite conclusion.

Spinal ependymomas: benefits of extent of resection for different histological grades

Although the World Health Organization (WHO) categorizes spinal ependymomas into three histological grades, difference in surgical outcomes between WHO grades I and II tumors are unclear. For these benign tumors, prognosis may be best determined by factors other than tumor grade alone, such as extent of resection. To analyze the effects of the extent of resection on different grades of spinal ependymomas, we performed a comprehensive literature review to identify adult spinal ependymoma patients who received surgical resection with a clearly identifiable WHO grade. A total of 175 patients were identified. While grade III tumors carried the worst prognosis as expected (p<0.001), grade I and II tumors did not differ significantly in outcomes following surgery. Overall, gross total resection (GTR, 68.7%, 114/166) provided significantly improved progression-free survival (PFS, p<0.001) and overall survival (OS, p=0.022) compared to the subtotal resection group. Surprisingly, the highest GTR rate was achieved for grade II tumors (78.8%, 78/99; p<0.001) followed by grade I (58.9%, 33/56) and grade III tumors (27.3%, 3/11). Interestingly, PFS was significantly improved by GTR for grade II tumors (p<0.001), but not for grade I (p=0.705). Similar trends, although not statistically significant, were found for OS. Our results show that while GTR provides the best overall outcomes, GTR is most effective for classic grade II ependymomas, but not for grade I ependymomas. Despite having a lower WHO grade, myxopapillary ependymomas have a lower GTR rate, and benefit less from GTR.

Prognosis by tumor location in adults with spinal ependymomas

OBJECT

Ependymomas are primary central nervous system tumors that occur more frequently in the spines of adults than they do there in children. Previous studies consist mainly of retrospective single-institutional experiences or case studies. In this study, a comprehensive literature review was performed on reported cases of spinal ependymoma treated with resection to determine whether tumor location along the spinal axis conveys important prognostic information.

METHODS

A PubMed search was performed to identify all papers that included data on patients with spinal ependymoma. Only cases involving adult patients who underwent ependymoma resection with a clearly reported tumor location were included for analysis. Tumor locations were separated into 6 groups: cervicomedullary, cervical, cervicothoracic, thoracic, thoracolumbar, and conus + cauda equina. Kaplan-Meier survival and Cox regression analyses were performed to determine the effect of tumor location on progression-free survival (PFS) and overall survival (OS).

RESULTS

A total of 447 patients who underwent resection of spinal ependymomas with clearly indicated location of tumor were identified. The most common locations of spinal ependymomas were the cervical (32.0%) and conus + cauda equina (26.8%) regions. The thoracolumbar and cervicomedullary regions had the fewest tumors (accounting for, respectively, 5.1% and 3.4% of the total number of cases). The conus + cauda equina and thoracolumbar regions had the highest percentage of WHO Grade I tumors, while tumors located above these regions consisted of mostly WHO Grade II tumors. Despite the tendency for benign grades in the lower spinal regions, PFS for patients with spinal ependymomas in the lower 3 regions (thoracic, thoracolumbar, conus + cauda equina) was significantly shorter (p < 0.001) than for those with tumors in the upper regions (cervicomedullary, cervical, cervicothoracic), but the difference in OS did not achieve statistical significance (p = 0.131).

CONCLUSIONS

Spinal ependymomas along different regions of spinal axis have different characteristics and clinical behaviors. Tumor grade, extent of resection, and PFS varied by tumor location (upper vs lower spinal regions), while OS did not. Recurrence rates were higher for the lower spinal cord tumors, despite a greater prevalence of lower WHO grade lesions, compared with upper spinal cord tumors, suggesting that tumor location along the spinal axis is an important prognostic factor.

Primary myxopapillary ependymoma of the fourth ventricle with cartilaginous metaplasia: a case report and review of the literature

Myxopapillary ependymoma (MPE), which is a benign histological subtype of ependymoma, is found predominantly in the cauda equina region. It occurs rarely in the brain and mostly as a metastatic deposit from a spinal lesion. The occurrence of primary intracranial MPE is exceptional, with only 11 cases reported to date. We report an additional case of intracranial MPE, which is the third reported case in the fourth ventricle. The tumor manifested in a 50-year-old lady, who presented with features of raised intracranial pressure. A gross total resection of the tumor was achieved. Histologically, the tumor had characteristic features of MPE with focal metaplastic cartilaginous deposit. On further evaluation, there was no evidence of a primary tumor in the spinal cord. Intracranial MPE needs further evaluation by craniospinal MRI to exclude an unrecognized primary in the spinal region, which could warrant surgical attention.

Surgical technique and outcomes in the treatment of spinal cord ependymomas: part II: myxopapillary ependymoma

BACKGROUND

Myxopapillary ependymomas usually occur in the filum terminale of the spinal cord.

OBJECTIVE

This report summarizes our experience treating myxopapillary ependymomas.

METHODS

The records of 34 patients (14 men, 20 women; mean age 45.5 years; age range, 14-88 years) who underwent resection of a myxopapillary ependymoma between 1983 and 2006 were reviewed for age, sex, tumor location, symptoms at diagnosis, duration of symptoms, treatment before presentation, extent of surgical resection, adjuvant therapy, length of follow-up, evidence of recurrence, and complications. Neurological examinations performed at presentation, immediately after surgery, and last follow-up were graded according to the McCormick grading scale.

RESULTS

The average duration of symptoms before diagnosis was 22.2 months. The most common symptom was pain followed by weakness, bowel/bladder symptoms, and numbness. The rate of gross total resection was 80%. All patients with a subtotal resection (20%) underwent postoperative radiation therapy. Presentation and outcomes of patients who underwent subtotal resection followed by radiation therapy were compared with those who underwent gross total resection. There was no significant difference in neurological grade between the groups at presentation or final follow-up. The overall recurrence rate was 10% (3/34 patients).

CONCLUSION

The goal of surgical treatment of myxopapillary ependymomas is resection to the greatest extent possible with preservation of function. In cases of subtotal resection, postoperative radiation therapy may improve outcome. If neurological function is maintained at treatment, these indolent lesions allow years of good function.

Primary Myxopapillary Ependymoma of the Medulla

OBJECTIVE

Myxopapillary ependymoma is a subclassification of ependymoma that is thought to be nearly exclusive to the conus medullaris or filum terminale. Primary intracerebral or brainstem myxopapillary ependymomas are rare.

CLINICAL PRESENTATION

An 8-year-old child presented with a 5-month history of nausea and vomiting and a 1-week history of headache. Magnetic resonance imaging revealed a nodular mass in the medulla with an associated cyst extending into the fourth ventricle.

INTERVENTION

A suboccipital craniotomy was performed, and a gross total resection of the lesion and cyst was achieved. Histological examination confirmed the diagnosis of myxopapillary ependymoma. A discussion of other reported cases of extraspinal myxopapillary ependymomas is presented.

CONCLUSION

This is the first report of a case of myxopapillary ependymoma, confirmed by histology, in the medulla. Although rare, myxopapillary ependymomas outside of the filum terminale do exist.