Intracranial retrograde dissemination in filum terminale myxopapillary ependymomas

Filum Terminale: A Comprehensive Review with Anatomical, Pathological, and Surgical Considerations

The conus medullaris is the distal tapering end of the spinal cord, and the filum terminale (FT) is regarded as a bundle of non-functional fibrous tissue; therefore, some scholars call it the spinal ligament, while others describe the human FT as "remnants of the spinal cord." It was later found that in the human spinal cord, the FT is composed of an intradural segment and an epidural segment, and the end of the FT is connected to the coccyx periosteum. Because some nerve tissue is also found in the FT, as research progresses, FT may have the potential for transplantation. A lack of exhaustive overviews on the FT in the present literature prompted us to conduct this review. Considering that a current comprehensive review seemed to be the need of the hour, herein, we attempted to summarize previous research and theories on the FT, elucidate its anatomy, and understand its pathological involvement in various diseases.

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.

Pathological Features of Brain Metastases

Metastases are the most common intracranial tumors in adults. Lung cancer, melanoma, renal cell carcinoma, and breast cancer are the most common primary tumors that metastasize to the brain. Improved detection of small metastases by MRI, and improved systemic therapy for primary tumors, resulted in increased incidence of brain metastasis. Advances in neuroanesthesia and neurosurgery have significantly improved the safety of surgical resection of brain metastases. Surgical approach and active management have become applicable for many patients. Subsequently, brain metastases diagnosis no longer equals palliative treatment. Moreover, the demand for diagnosing brain masses has increased with its associated challenges.

Preoperative Intracranial Dissemination of Spinal Myxopapillary Ependymoma Attributed to Tumor Hemorrhage

BACKGROUND

Spinal myxopapillary ependymoma (SME), generally considered a benign entity, can exhibit brain and whole-spine metastases as well as local recurrence after surgery. However, the presence of preoperative retrograde intracranial dissemination at the time of diagnosis is very rare.

CASE DESCRIPTION

We report a case of SME in a 22-year-old man who presented with acute exacerbation of chronic back pain shooting down both thighs and weakness in both legs. Magnetic resonance imaging of the brain and whole spine showed an enhancing mass occupying the majority of the spinal canal at the L1-L2 level and multiple foci dissemination, including in the right pons, lateral midbrain, and occipital lobe, and at the C7, Th6, L4, and S2 levels of the spinal canal at the time of diagnosis. On gross total removal of the dominant tumor located at the L1-L2 level, severe intradural arachnoiditis and syrinx filled with xanthochromic cerebrospinal fluid was noted, indicating the presence of previous tumor hemorrhage. Histopathologic analysis of the tumor supported SME diagnosis, and <1% of cells showed Ki-67 expression. We speculated that distant retrograde dissemination could have been attributed to metastatic spread through cerebrospinal fluid caused by tumor hemorrhage, which may explain distant dissemination despite low expression of Ki-67.

CONCLUSIONS

Screening of the whole brain and spine at the time of diagnosis is imperative when tumor is detected at any level of the neuraxis. The present case of SME with a preoperative intracranial lesion is the fifth case documented in the medical literature.

MYXOPAPILLARY EPENDYMOMA OF THE SPINAL CORD IN ADULTS: A REPORT OF PERSONAL SERIES AND REVIEW OF LITERATURE

Myxopapillary ependymomas (MPE) of the spinal cord are slow-growing benign tumors most frequently found in adults between 30 and 50 years of age. They arise from the ependyma of the filum terminale and are located in the area of the medullary conus and cauda. The recommended treatment option is gross total resection, while patients undergoing subtotal resection usually require radiotherapy. Complete resection without capsular violation can be curative and is often accomplished by simple resection of the filum above and below the tumor mass. Nevertheless, dissemination and distant treatment failure may occur in approximately 30% of the cases. In this paper, we propose an original MPE classification, which is based upon our personal series report concerned with tumor location and its correlation with the extent of resection. We also provide literature review, discussing surgical technique, tumor recurrence rate and dissemination, and adjuvant treatment. In conclusion, our findings suggest that MPE management based on the proposed 5-type tumor classification is favorable when total surgical resection is performed in carefully selected patients. Yet, further studies on a much broader model is obligatory to confirm this.

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.

Invasive myxopapillary ependymoma of the lumbar spine: A case report

BACKGROUND

Myxopapillary ependymomas are rare spinal tumours. Although histologically benign, they have a tendency for local recurrence.

CASE SUMMARY

We describe a patient suffering from extra- and intradural myxopapillary ependymoma with perisacral spreading. He was treated with subtotal resection and postoperative radiation therapy. After treatment, he experienced slight sphincter disorders and lumboischialgic pain with no motor or sensory disturbances. Eight months later, a tumour regression was documented. The patient is still followed-up regularly.

CONCLUSION

Lumbar myxopapillary ependymomas may present with lumbar or radicular pain, similar to more trivial lesions. Magnetic resonance imaging (MRI) is the primary modality for diagnosis. The treatment aim is to minimize both tumour and therapy-related morbidity and to involve different treatment modalities.

Management and Outcome Analysis of Conus and Filum ependymoma: A Tertiary Center Study

Background

Spinal ependymomas constitute approximately 2%-8% of primary adult central nervous system tumors. Authors analyzed demographic, clinical, radiological, surgical, and histopathological factors which correlated with the postoperative neurological outcome of patients who underwent surgery for conus and filum ependymoma (CFE).

Materials and Methods

A retrospective analysis of 31 patients regarding clinical feature, imaging study, surgical management, and McCormick grading system for assessing functional neurological status was carried out, who underwent surgical management for CFE between January 2009 and April 2014. Final neurological outcome at follow-up period was correlated with various factors in search to find out probable prognostic factors affecting final neurological outcome following surgical management.

Results

The myxopapillary ependymoma was observed in 55% of cases (n = 17), while 39% cases (n = 12) had Grade II ependymoma and rest 6% (n = 2) cases had anaplastic ependymomas. The mean age was 30 years (range 7-60 years) with male to female ratio of 1:0.82. Patients predominantly presented with pain (80.65%); mean duration of symptoms was 28.61 months. Only, the preoperative McCormick grade was found to be the statistically significant prognostic factor (P = 0.045), affecting neurological outcome however, the age, sex, duration of symptoms, location of the tumor, extent of the tumor, extradural spread, degree of surgical excision, vascularity of tumor, and histopathological World Health Organization grades were not found to be significant prognostic factors in the current study.

Conclusion

The preoperative McCormick score was found to be the only statistically significant factor predicting the functional and neurological outcome after surgery, so surgical treatment should be offered early in the course of the disease to provide chance of preservation and good neurological recovery.

Differentiation of spinal myxopapillary ependymomas from schwannomas by contrast-enhanced MRI

BACKGROUND

Spinal myxopapillary ependymomas (MPEs) and schwannomas (SCHs) are both frequently located at the conus and caudal regions. The differentiation between MPEs and SCHs before surgery is crucial. Signal patterns of MPEs and SCHs on T2-weighted (T2W) magnetic resonance imaging (MRI) are diverse. Gadolinium (Gd+)-enhanced areas in MRI scans areas are areas where tumor cells are abundant. Therefore, investigating these enhanced areas should facilitate the differentiation. This study aimed to evaluate Gd+ areas in MRI scans in spinal MPEs and SCHs. Furthermore, the relation between MRI pattern and pathological features was investigated.

METHODS

In total, 41 patients with spinal MPEs (n = 7) or SCHs (n = 34) around the conus medullaris were included. SCHs were classified per the Gd+ area of the tumor on T1-weighted (T1W) contrast images, into Gd+ areas with T2W hyperintensity (Gd+/T2high) (n = 4, 11.8%) or Gd+ areas with T2W isointensity (Gd+/T2iso) (n = 30, 88.2%). Four patients with Gd+/T2iso were selected randomly for comparison. In three patient groups, T2 values at the Gd+ area and tumor cell density as measured by HE stains (cell density) were compared.

RESULTS

T2 values at the Gd+ area was higher in patients with MPE than in those with SCH with Gd+/T2high, and significantly higher than that in patients with SCH with Gd+/T2iso. Cell density was significantly lower in patients with MPEs than for those with SCHs with Gd+/T2high, and those with SCHs with Gd+/T2iso.

CONCLUSION

The evaluation of the Gd+ area proved useful because it excludes cysts or necrotic portions. If the Gd+ area is hyperintense on T2WI, MPEs can be suspected. If the Gd+ area is isointense on T2WI, SCHs can be suspected. There were several exceptional cases of SCH with a Gd+ area that was hyperintense on T2WI. This could be explained by pathological findings showing low cell density, as is typical for MPEs.

Metastases of spinal myxopapillary ependymoma: unique characteristics and clinical management

OBJECTIVE

Myxopapillary ependymoma is a benign WHO Grade I tumor most commonly located in the conus–cauda equina region of the spine. Although this tumor is defined by an overall excellent survival, dissemination throughout the whole neuraxis occurs frequently. The current study evaluated the clinical characteristics and significance of myxopapillary ependymoma metastases.

METHODS

Patients who underwent surgery from 2005 to 2015 for treatment of spinal myxopapillary ependymoma were included in the study. Charts were reviewed for primary tumor symptoms and initial treatment, local recurrence, response to salvage therapy, and presence and behavior of distant metastases.

RESULTS

Nineteen patients with spinal myxopapillary ependymoma were included in the study (52.6% female). The median age at first diagnosis was 32 years old (range 9–58 years old), and 26.3% were ≤ 18 years old. The median follow-up of all included patients was 48 months (range 6–456 months). Of the primary tumors, 84.2% were located in the lower thoracic or upper lumbar spine, spanning 1–3 levels in 94.7%. All patients underwent surgery for initial treatment: in 78.9% a gross-total resection (GTR) was achieved, with adjuvant radiation therapy (RT) in 20%. Of the 21.2% who underwent a subtotal resection (STR), 75% underwent postoperative RT. Tumor progression was noted in 26.3% of patients after a median 36-month follow-up (range 12–240 months). In 57.9% of patients, distant metastases were found, of which 36.4% were present at initial diagnosis. Further metastases occurred within a median of 20 months (range 2–360 months). Following a diagnosis of metastatic tumor, 72.7% did not show progression and no symptoms were observed during a median follow-up of 36 months (range 6–216 months). Metastases occurred in all parts of the neuroaxis, but were principally localized in the thoracic and sacral spine in 38.9% and 33.3%, respectively; the brain was involved in 11.1%. In 54.5%, more than 1 level was affected. Overall survival was 100% with an excellent clinical and neurological outcome in 78.9% of cases.

CONCLUSIONS

Metastatic dissemination within the CNS can be observed in many patients with myxopapillary ependymoma. GTR of the primary tumor should be the primary treatment goal, and additional RT is recommended after STR. For distant metastases of myxopapillary ependymoma without clinical manifestation, close clinical and MRI follow-up represents a sufficient strategy because most of the metastases remain asymptomatic and do not show progression over time. Additional resection or irradiation as salvage therapy would be recommended if metastases become symptomatic.

Remarkable efficacy of temozolomide for relapsed spinal myxopapillary ependymoma with multiple recurrence and cerebrospinal dissemination: a case report and literature review

PURPOSE

Myxopapillary ependymomas are intradural tumors which grow from the terminal filum of the spinal cord. Although they are classified as WHO grade I, they sometimes cause cerebrospinal fluid dissemination or local recurrence. In this report, we describe a case in that temozolomide (TMZ) showed remarkable efficacy on a recurrent spinal myxopapillary ependymoma.

CASE REPORT

A 26-year-old female underwent resection of an intradural myxopapillary ependymoma at L5 initially. Although an en bloc total resection, including the capsule, could be achieved, she needed two additional tumor resection surgeries with postoperative radiotherapy at L4 and at L3 (2 and 6 years after the initial surgery, respectively). Moreover, 4 years after the initial surgery, a disseminated metastatic tumor occurred at T11/12 and local radiotherapy was not effective. After the third surgery, an aggressive adjuvant therapy was necessary because there was a high risk of another recurrence. Therefore, TMZ was administered for 1 year. After 6 months of TMZ treatment, remarkably, the disseminated metastatic tumor at T11/12 had disappeared completely. Presently, 6 years after finishing the TMZ treatment, the follow-up MRI has shown no recurrence in the brain and whole spine.

CONCLUSIONS

TMZ is usually used in the treatment of glioblastoma and, recently, it has been reported to be effective for the lower grade spinal gliomas including spinal intramedullary ependymomas. However, for myxopapillary ependymomas, there has been no report that TMZ is effective. According to our results, TMZ could be one of the possible candidates for adjuvant therapy in multiple recurrent myxopapillary ependymomas.

Benign ependymoma with extensive intracranial and spinal cerebrospinal fluid dissemination: case report and literature review

Myxopapillary ependymoma (MPE) is a rare variant of ependymoma that is most commonly located in the cauda equina and filum terminale. We present a case of 23-year-old man diagnosed with MPE in the fourth ventricle and sacral canal area with extensive disseminated lesions along the cerebrospinal ventricular system. Additionally, a molecular pathological diagnosis was performed. The patient underwent a craniotomy and a lumbar laminectomy. In the course of 18 months of follow-up, the patient have recovered very well.

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.

Outcomes following myxopapillary ependymoma resection: the importance of capsule integrity

OBJECT While extent of resection has been shown to correlate with outcomes after myxopapillary ependymoma (MPE) resection, the effect of capsular violation has not been well studied. The role of adjuvant radiation also remains controversial. In this paper the authors' goals were to evaluate outcomes following resection of MPE based on intraoperative capsular violation and to explore the role of adjuvant radiotherapy in cases of capsular violation. METHODS A retrospective review of patients undergoing resection of MPE at 2 academic institutions between 1990 and 2013 was performed. Cases with dissemination at presentation, less than 12 months of follow-up, or incomplete records were excluded. Extent of resection was defined as en bloc if all visible tumor was removed without capsular violation, gross-total resection (GTR) if all visible tumor was removed, but with capsular violation, and subtotal resection (STR) if a known residual was left at the time of surgery. Postoperative MR images were reviewed to confirm the extent of resection. Primary outcomes were progression-free survival (PFS) and overall recurrence rates. The effects of extent of resection, capsular violation, and adjuvant radiotherapy on recurrence rates and PFS were analyzed using Kaplan-Meier statistics. Associations between recurrence and preoperative variables were evaluated using Fisher exact methods and t-tests where appropriate. RESULTS Of the 107 patients reviewed, 58 patients (53% were male) met inclusion criteria. The mean age at surgery was 40.8 years (range 7-68 years). The median follow-up was 51.5 months (range 12-243 months). Extent of resection was defined as en bloc in 46.5% (n = 27), GTR in 34.5% (n = 20), and STR in 18.9% (n = 11). No recurrences were noted in the en bloc group, compared with 15% (n = 3) and 45% (n = 5) in the GTR and STR groups. En bloc resection was achieved most frequently in tumors involving the conus. Twelve patients (20%) underwent adjuvant radiotherapy following either STR or GTR. The overall recurrence rate was 13.8% (n = 8), and the 5-year PFS was 81%. Capsular violation was associated with a higher recurrence rate (p = 0.005). Adjuvant radiotherapy showed a nonsignificant trend of lower recurrence rates (16.7% vs 31.6%, p = 0.43) and longer PFS at 5 years (83.3% vs 49.9%, p = 0.16) in cases of capsular violation. CONCLUSIONS A strong correlation between capsular violation and recurrence was found following removal of MPE and should be assessed when defining extent of resection in future studies. Although the use of adjuvant radiotherapy in cases of capsular violation showed a trend toward improved PFS, further investigation is needed to establish its role as salvage therapy also appears to be effective at halting disease progression.

Concomitant Double Tumors of Myxopapillary Ependymoma Presented at Cauda Equina-Filum Terminale in Adult Patient

A 32-year-old man presented with gradually increasing bilateral buttock pain. He had intermittent claudication. Multiple, homogenously enhanced intradural extramedullary lesions at L2-L3 and L5-S1 levels were observed on magnetic resonance imaging. The tumors were debulked and were removed in piecemeal pattern until they had completely been resected. Histopathological examination of the surgical specimens confirmed that both tumors were myxopapillary ependymomas (MPE). MPE presenting as concomitant double tumor at conus-cauda-filum level are very rare. This kind of presentation could not be directly considered as dissemination, since both tumors were in the site of classical origin of MPE. Ten cases of double spinal MPEs have been reported to date. Including the present case, analysis of the 11 patients revealed some facts. There is a male predominance, which is opposite to the ependymomas that are commonly observed in females. Median age at presentation is 15 years. Most pronounced symptom is low back pain that sometimes radiates to lower extremities. Surgical approach was aimed in all tumors, which could be succeeded in all tumors except one. Adjuvant radiation therapy was applied in 5 patients. No recurrences have been reported after surgery or surgery + radiotherapy regimens.

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.

The nature of double concomitant myxopapillary ependymoma: report of a case

Myxopapillary ependymomas are almost exclusively seen at the conus medullaris/filum terminale/cauda equina region, usually as solitary space-occupying lesions. The authors report the case of a 14-year-old boy with double concomitant myxopapillary ependymoma, proximal and caudal on the filum terminale in which a totally gross removal was achieved in two stages. This presentation is rare and, so far, we have known just three similar cases that were previously reported in children. The true nature of these lesions is controversial, and while some argue that they are related to metastatic seeding, others consider them independent lesions developing synchronously. A review on dissemination of spinal myxopapillary ependymomas was done.

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.

Pathology of Spinal Ependymomas

BACKGROUND:

Ependymomas constitute approximately 40% of primary intraspinal tumors. Current World Health Organization (WHO) grading may not correlate with observed progression-free survival (PFS).

OBJECTIVE:

This retrospective study of prospectively collected data examines whether PFS is influenced by the histological grade or by the extent of resection. It also analyzes the usage and effectiveness of postoperative adjuvant radiotherapy.

METHODS:

We reviewed 134 consecutive patients with ependymomas of all grades. Pathology slides were re-reviewed and the histological grades were confirmed by a single neuropathologist. Postoperative residual or recurrence was evaluated with follow-up magnetic resonance imaging.

RESULTS:

There were 85 male and 49 female patients, ranging from 10 to 79 (median 41) years of age. Thirty patients had WHO grade I tumors, 101 had grade II tumors, and 3 had grade III tumors. Kaplan-Meier analysis of PFS demonstrated a mean duration of 6 years for grade I, 14.9 years for grade II, and 3.7 years for grade III (P &lt; .001). In grade II ependymomas, mean PFS was 11.2 years with subtotal resection and 17.8 years with gross total resection (P &lt; .01). PFS of patients who underwent subtotal resection was not significantly changed by adjuvant radiotherapy (P &lt; .36).

CONCLUSION:

Patients with grade II ependymoma have significantly longer PFS than patients with grade I ependymoma. The extent of resection did not affect PFS in grade I ependymoma but it did in grade II. Contrary to its higher grade, WHO grade II ependymoma carries a better prognosis than WHO grade I ependymoma.

Anaplastic ependymoma with holocordal and intracranial meningeal carcinomatosis and holospinal bone metastases

BACKGROUND AND IMPORTANCE

Ependymomas are the most frequent intramedullary neoplasms in adult patients. Anaplastic histology, extramedullary location, meningeal dissemination at initial diagnosis, and extraneural metastases are rare findings. We describe a case of extramedullary anaplastic ependymoma that presented with holocordal and intracranial leptomeningeal carcinomatosis and bone metastases in all the vertebral bodies and the sternum. Such an aggressive dissemination at initial diagnosis has not been previously reported.

CLINICAL PRESENTATION

A 36-year-old woman presented with headache, multiple cranial nerve palsies, visual hallucinations, confusion, hemiparesis, hemihipoestesia, episodes of disconnection, and toxic syndrome. Magnetic resonance imaging and positron emission tomography scan revealed leptomeningeal carcinomatosis in the brainstem, the cerebellum, and along the whole spinal cord. Various nodular, intradural extramedullary lesions were present at multiple dorsal and lumbar levels. Metastatic bone disease affected all the vertebral bodies and various extraspinal bones. An intradural and bone biopsy was performed at L4, providing the diagnosis of anaplastic ependymoma (World Health Organization grade III) with focal neuronal differentiation. Despite chemotherapy, the patient's symptoms quickly progressed, and she died 7 weeks after diagnosis.

CONCLUSION

To our knowledge, there are no previous descriptions of ependymomas with this extensive leptomeningeal, spinal, intracranial, and extraneural dissemination at clinical onset. Bone metastases in spinal ependymoma have not been previously reported.

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.

Mortality is higher in patients with leptomeningeal metastasis in spinal cord tumors

Spinal cord tumors are a rare neoplasm of the central nervous system (CNS). The occurrence of metastases is related to poor prognosis. The authors analyzed one series of metastasis cases and their associated mortality.

METHODS

Clinical characteristics were studied in six patients with intramedullary tumors with metastases in a series of 71 surgical cases.

RESULTS

Five patients had ependymomas of which two were WHO grade III. The patient with astrocytoma had a grade II histopathological classification. Two patients required shunts for hydrocephalus. The survival curve showed a higher mortality than the general group of patients with no metastases in the CNS (p<0.0001).

CONCLUSION

Mortality is elevated in patients with metastasis and greater than in patients with only primary lesions. The ependymomas, regardless of their degree of anaplasia, are more likely to cause metastasis than spinal cord astrocytomas.

EGFR as a predictor of relapse in myxopapillary ependymoma

Myxopapillary ependymoma (MPE) is a rare subtype of ependymoma in children. Though classified as a Grade I tumor, their unpredictable behavior and propensity for local and disseminated recurrence poses a therapeutic challenge. Till date no predictive molecular markers exist for such recurrence, especially with dissemination. We demonstrated that Epidermal Growth Factor Receptor (EGFR) expression was seen in relapsed MPE both at diagnosis and at recurrence and none in the nonrecurring tumors. This finding suggests EGFR could be a predictive biomarker for recurrence in MPE.

Ependymomas of the filum terminale: The role of surgery and radiotherapy

Background:

Ependymomas of the filum terminale (EFT) form a specific and relatively uncommon subtype of spinal cord ependymomas. Most series in the literature are small, spanning a large time period. Up to date no consensus has been reached about the optimal treatment of these lesions. Some authors promote postoperative radiotherapy for all cases, others advocate postoperative radiotherapy only when a subtotal resection is performed or when metastasis are apparent.

Methods:

We performed a retrospective analysis of 22 patients with an EFT (mean age at diagnosis of 35.6 years).

Results:

In all patients (9/22) with lesions smaller than 4.5 cm no metastases were present and a complete resection could be obtained. No adjuvant radiotherapy was performed and at latest follow they had an excellent outcome. In our series, these initial tumor characteristics were more important regarding prognosis than either histology or treatment-related factors. For the larger tumors, total resection was obtained less frequently, more dissemination was diagnosed and a worse outcome was scored. Radiotherapy if indicated did lead to an acceptable disease control.

Conclusion:

In every case of EFT, an individual treatment protocol has to be outlined, but if an EFT is relatively small and can be resected completely, we would advocate to withhold radiotherapy.

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.

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.

Multiple intradural-extramedullary ependymomas: proven dissemination by genetic analysis

This 45-year-old woman was admitted with neck and back pain and difficulty in ambulation that had been progressively worsening for 2 years. Admission MR imaging revealed a cervicomedullary junction tumor and 2 intradural-extramedullary spinal tumors located separately at the levels of T5-6 and T8-9. All masses were successfully resected in a 2-stage operation. Histopathological examination of the surgical specimens revealed that all the lesions were ependymomas. Genetic analysis was performed to determine if the tumors were related. Conventional cytogenetics, multiplex fluorescence in situ hybridization (M-FISH), interphase-FISH specific to 22q11, and epidermal growth factor receptor loci analyses of the tumor samples revealed that the lesions originated from the same primary tumor. Although 3 simultaneous tumors in different compartments of the neural axis were diagnosed as ependymoma by histopathological examination, it was not possible to be sure if their multiplicity was due to spread of tumor cells via CSF or if it was due to multicentric foci. Thus, genetic analysis of the tumor samples is essential to confirm the exact mechanism of development of multiple ependymomas.

Intramedullary papillary ependymoma with choroid plexus differentiation and cerebrospinal fluid dissemination to the brain

This 8-year-old girl presented with a papillary ependymoma in the thoracic spinal cord. Resection was followed by recurrence at the primary site and later in the lumbosacral thecal sac, followed by cerebrospinal fluid dissemination to the brain approximately 5 years after her initial presentation. The tumor showed cytological and immunohistochemical features overlapping those of classic ependymomas and choroid plexus tumors similar to those seen in uncommon supratentorial papillary ependymomas, also known as papillary tumors of the pineal region. The histopathological and clinical courses of this rare spinal papillary ependymoma exhibiting mixed ependymal and choroid plexus-like differentiation are discussed.

Long-term surgical outcomes for myxopapillary ependymomas of the cauda equina

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To evaluate our treatment strategy for myxopapillary ependymomas of the cauda equina.

SUMMARY OF BACKGROUND DATA

Some patients with myxopapillary ependymoma develop cerebrospinal fluid (CSF) dissemination leading to poor prognosis. Because of the rarity of this tumor, there is no consensus on its optimal treatment options and prognosis.

METHODS

We reviewed 25 cases of myxopapillary ependymomas, treated surgically between 1972 and 2005. The mean postoperative follow-up period was 10.4 years. The effects of surgical margins at surgery and postoperative radiotherapy on tumor recurrence and prognosis were investigated.

RESULTS

In 15 patients, total resection achieved (6 cases of en bloc resection without postoperative radiation, and in 9 cases piecemeal resection) was followed by whole brain and spinal cord radiation or local irradiation. Fourteen of these patients survived without tumor recurrence. In 1 case of total resection without radiotherapy, the tumor capsule was violated intraoperatively and local recurrence occurred 2 years after surgery. In 4 patients, the tumors were removed subtotally. Of these, 2 patients who received radiation (24 Gy) only to the whole brain and spinal cord developed recurrence, and 2 who received whole brain and spinal cord radiation (24 Gy) supplemented with local radiation (46 Gy) developed no recurrence. The remaining 6 patients received partial resection after local radiation (40-50 Gy) alone, and all 6 died of CSF dissemination.

CONCLUSION

The results of the present study indicate that the surgical margin obtained at the initial surgery and the extent and amount of postoperative radiation can be crucial factors determining the prognosis of patients with myxopapillary ependymoma. Although this tumor is histologically benign, CSF dissemination can occur once tumor capsule is violated, before or during surgery. Therefore, early diagnosis is essential, and a therapeutic strategy including radiotherapy, on the assumption that this tumor is malignant, should be established.

Ependymal tumors

Ependymomas represent a heterogeneous group of glial tumors whose biological behavior depends on various histological, molecular, and clinical variables. The scope of this chapter is to review the clinical and histo-logical features as well as the molecular genetics of ependymomas with special emphasis on their influence on tumor recurrence and prognosis. Furthermore, potential molecular targets for therapy are outlined.