Clinical characteristics and long-term surgical outcome of spinal myxopapillary ependymoma: a French cohort of 101 patients

Outcomes and Pattern of Care for Spinal Myxopapillary Ependymoma in the Modern Era-A Population-Based Observational Study

(1) Background: Myxopapillary ependymoma (MPE) is a rare tumor of the spine, typically slow-growing and low-grade. Optimal management strategies remain unclear due to limited evidence given the low incidence of the disease. (2) Methods: We analyzed data from 1197 patients with spinal MPE from the Surveillance, Epidemiology, and End Results (SEER) database (2000-2020). Patient demographics, treatment modalities, and survival outcomes were examined using statistical analyses. (3) Results: Most patients were White (89.9%) with a median age at diagnosis of 42 years. Surgical resection was performed in 95% of cases. The estimated 10-year overall survival was 91.4%. Younger age (hazard ratio (HR) = 1.09, p < 0.001) and receipt of surgery (HR = 0.43, p = 0.007) were associated with improved survival. Surprisingly, male sex was associated with worse survival (HR = 1.86, p = 0.008) and a younger age at diagnosis compared to females. (4) Conclusions: This study, the largest of its kind, underscores the importance of surgical resection in managing spinal MPE. The unexpected association between male sex and worse survival warrants further investigation into potential sex-specific pathophysiological factors influencing prognosis. Despite limitations, our findings contribute valuable insights for guiding clinical management strategies for spinal MPE.

Utility of Multimodal Intraoperative Neuromonitoring for Excision of Filum Terminale Ependymoma in Close Proximity to Conus

Myxopapillary ependymoma are well circumscribed tumours arising mainly from conus medullaris (CM) and filum terminale (FT), typically presenting at median age of 39 years.1 Owing to its aggressive clinical behaviour including cerebrospinal fluid dissemination and local recurrence, it is classified as grade 2 in World Health Organisation Central Nervous System 5 Classification.2 Gross total resection without capsular violation is critical, as subtotal resection is associated with local recurrence.3 The FT comprises intradural filum terminale (iFT) and extradural filum terminalecomponents with iFT extending from the inferior tip of the CM to coccyx.4 The iFT-CM junction is a transitional zone; with neural tissue being incrementally replaced by fibrous tissue of filum, gradually converging to a pure nonneural FT.5 Achieving gross total resection is challenging for intramedullary FT myxopapillary ependymoma in proximity to conus, necessitating neuromonitoring to preserve vital CM functions. We present a case of 33-year-old male with 6 months of nocturnal back pain and bilateral lower limb without neurological deficits. Preoperative MRI revealed a T2 hyperintense, heterogeneously contrast enhancing intradural extramedullary mass at L1 vertebral level.

Development of a novel prediction model for differential diagnosis between spinal myxopapillary ependymoma and schwannoma

Spinal myxopapillary ependymoma (MPE) and schwannoma represent clinically distinct intradural extramedullary tumors, albeit with shared and overlapping magnetic resonance imaging (MRI) characteristics. We aimed to identify significant MRI features that can differentiate between MPE and schwannoma and develop a novel prediction model using these features. In this study, 77 patients with MPE (n = 24) or schwannoma (n = 53) who underwent preoperative MRI and surgical removal between January 2012 and December 2022 were included. MRI features, including intratumoral T2 dark signals, subarachnoid hemorrhage (SAH), leptomeningeal seeding, and enhancement patterns, were analyzed. Logistic regression analysis was conducted to distinguish between MPE and schwannomas based on MRI parameters, and a prediction model was developed using significant MRI parameters. The model was validated internally using a stratified tenfold cross-validation. The area under the curve (AUC) was calculated based on the receiver operating characteristic curve analysis. MPEs had a significantly larger mean size (p = 0.0035), higher frequency of intratumoral T2 dark signals (p = 0.0021), associated SAH (p = 0.0377), and leptomeningeal seeding (p = 0.0377). Focal and diffuse heterogeneous enhancement patterns were significantly more common in MPEs (p = 0.0049 and 0.0038, respectively). Multivariable analyses showed that intratumoral T2 dark signal (p = 0.0439) and focal (p = 0.0029) and diffuse enhancement patterns (p = 0.0398) were independent factors. The prediction model showed an AUC of 0.9204 (95% CI 0.8532-0.9876) and the average AUC for internal validation was 0.9210 (95% CI 0.9160-0.9270). MRI provides useful data for differentiating spinal MPEs from schwannomas. The prediction model developed based on the MRI features demonstrated excellent discriminatory performance.

Spinal Ependymomas: An Updated WHO Classification and a Narrative Review

Ependymomas are neuroepithelial tumors that develop from ependymal cells found in the brain parenchyma and can spread to any part of the spinal cord. Three to six percent of all malignancies affecting the central nervous system (CNS) are ependymomas. Even the most talented surgeons are challenged by spinal cord ependymomas; as a result, research into this clinical phenomenon should continue. Since 1979, the World Health Organization (WHO) has published a classification and grading system for CNS malignancies to ensure consistent diagnostic standards worldwide. The WHO prepared an update on these tumors, paying particular attention to molecular techniques to categorize the therapeutic management of each patient with greater accuracy and clarity. We thoroughly reviewed the literature on the epidemiology, etiology, diagnosis, and treatment of spinal ependymomas since there has not been a recent review of these tumors. This included modifications to the 2021 WHO Classification of Tumors of the Central Nervous System.

Predictors of Progression-Free Survival in Patients With Spinal Intramedullary Ependymoma: A Multicenter Retrospective Study by the Neurospinal Society of Japan

BACKGROUND AND OBJECTIVES

Ependymoma is the most common spinal intramedullary tumor. Although clinical outcomes have been described in the literature, most of the reports were based on limited numbers of cases or been confined to institutional experience. The objective of this study was to analyze more detailed characteristics of spinal intramedullary ependymoma (SIE) and provide clinical factors associated with progression-free survival (PFS).

METHODS

This retrospective observational multicenter study included consecutive patients with SIE in the cervical or thoracic spine treated surgically at a total of 58 institutions between 2009 and 2020. The results of pathological diagnosis at each institute were confirmed, and patients with myxopapillary ependymoma, subependymoma, or unverified histopathology were strictly excluded from this study. Outcome measures included surgical data, surgery-related complications, postoperative systemic adverse events, postoperative adjuvant treatment, postoperative functional condition, and presence of recurrence.

RESULTS

This study included 324 cases of World Health Organization grade II (96.4%) and 12 cases of World Health Organization grade III (3.6%). Gross total resection (GTR) was achieved in 76.5% of cases. Radiation therapy (RT) was applied after surgery in 16 cases (4.8%), all of which received local RT and 5 of which underwent chemotherapy in combination. Functional outcomes were significantly affected by preoperative neurological symptoms, tumor location, extent of tumor resection, and recurrence. Multivariate regression analysis suggested that limited extent of tumor resection or recurrence resulted in poor functional outcomes. Multiple comparisons among the groups undergoing GTR, subtotal resection and biopsy, or partial resection of the tumor showed that the probability of PFS differed significantly between GTR and other extents of resection.

CONCLUSION

When GTR can be safely obtained in the surgery for SIE, functional maintenance and longer PFS can be expected.

Clinical management and prognosis of spinal myxopapillary ependymoma: a single-institution cohort of 72 patients

PURPOSE

Myxopapillary ependymoma (MPE) was classified as grade 2 tumor in the 2021 World Health Organization central nervous system classification because of its high recurrence probability. This study aimed to investigate predictive factors and management of tumor recurrence.

METHODS

Seventy-two patients with spinal MPE underwent initial surgical treatment at our hospital between 2011 and 2021. Kaplan-Meier curves and Cox regression were used to analyze the correlation between clinical variables and progression-free survival (PFS).

RESULTS

The median age at diagnosis was 33.5 years (range 8-60 years). Twenty-one patients (29.2%) had preoperative spinal drop metastases. Gross total resection (GTR) was performed in 37 patients (51.4%). The median follow-up was 7.2 years, and the follow-up rate was 88.9% (64 of 72 cases). Twelve of the 64 patients (18.9%) relapsed, and preoperative drop metastasis occurred in 7 patients (58.3%). The estimated 5-year and 10-year PFS rates were 82% and 77%, respectively. Univariate analysis showed that GTR was associated with improved PFS (hazard ratio [HR] 0.149, p = 0.014), while preoperative drop metastasis (HR 3.648, p = 0.027) and tumor involvement sacrococcygeal region (HR 7.563, p = 0.003) were associated with tumor recurrence. Adjuvant radiotherapy (RT) was significantly associated with improved PFS in patients with preoperative drop metastasis (p = 0.039).

CONCLUSION

Complete surgical resection under the premise of protecting neurological function is an important factor in reducing spinal MPE recurrence. Adjuvant RT is recommended when the tumor invades the capsule with preoperative drop metastasis or adhesion to the nerve and cannot reach GTR.

Ependymoma: Evaluation and Management Updates

PURPOSE OF REVIEW

To review state of art and relevant advances in the molecular genetics and management of ependymomas of children and adults.

RECENT FINDINGS

Ependymomas may occur either in the brain or in the spinal cord. Compared with intracranial ependymomas, spinal ependymomas are less frequent and exhibit a better prognosis. The new WHO classification of CNS tumors of 2021 has subdivided ependymomas into different histomolecular subgroups with different outcome. The majority of studies have shown a major impact of extent of resection; thus, a complete resection must be performed, whenever possible, at first surgery or at reoperation. Conformal radiotherapy is recommended for grade 3 or incompletely resected grade II tumors. Proton therapy is increasingly employed especially in children to reduce the risk of neurocognitive and endocrine sequelae. Craniospinal irradiation is reserved for metastatic disease. Chemotherapy is not useful as primary treatment and is commonly employed as salvage treatment for patients failing surgery and radiotherapy. Standard treatments are still the mainstay of treatment: the discovery of new druggable pathways will hopefully increase the therapeutic armamentarium in the near future.

Comprehensive profiling of myxopapillary ependymomas identifies a distinct molecular subtype with relapsing disease

BACKGROUND

Myxopapillary ependymoma (MPE) is a heterogeneous disease regarding histopathology and outcome. The underlying molecular biology is poorly understood, and markers that reliably predict the patients' clinical course are unknown.

METHODS

We assembled a cohort of 185 tumors classified as MPE based on DNA methylation. Methylation patterns, copy number profiles, and MGMT promoter methylation were analyzed for all tumors, 106 tumors were evaluated histomorphologically, and RNA sequencing was performed for 37 cases. Based on methylation profiling, we defined two subtypes MPE-A and MPEB, and explored associations with epidemiological, clinical, pathological, and molecular characteristics of these tumors.

RESULTS

MPE-A occurred at a median age of 27 years and were enriched with tumors demonstrating papillary morphology and MGMT promoter hypermethylation. Half of these tumors could not be totally resected, and 85% relapsed within 10 years. Copy number alterations were more common in MPE-A. RNA sequencing revealed an enrichment for extracellular matrix and immune system-related signatures in MPE-A. MPE-B occurred at a median age of 45 years and included many tumors with a histological diagnosis of WHO grade II and tanycytic morphology. Patients within this subtype had a significantly better outcome with a relapse rate of 33% in 10 years (p=3.4e-06).

CONCLUSIONS

We unraveled the morphological and clinical heterogeneity of MPE by identifying two molecularly distinct subtypes. These subtypes significantly differed in progression-free survival and will likely need different protocols for surveillance and treatment.

Updates in the classification of ependymal neoplasms: The 2021 WHO Classification and beyond

Ependymal neoplasms occur at all ages and encompass multiple tumor types and subtypes that develop in the supratentorial compartment, the posterior fossa, or the spinal cord. Clinically, ependymomas represent a very heterogeneous group of tumors from rather benign subependymomas to very aggressive and often deadly childhood ependymomas of the posterior fossa. Newly identified biological markers and classification schemes, e. g. based on global DNA methylation profiling, have led to the definition of 10 types of ependymal tumors and an improved prediction of patients’ outcome by applying the new classification system. While the exact genetic basis for several ependymoma types still remains unclear, the knowledge about ependymoma driving events has significantly increased within the last decade and contributed to a classification based on molecular characteristics and localization rather than histological features alone. Convincing evidence is now pointing towards gene fusions involving ZFTA or YAP1 causing the development of supratentorial ependymomas. Also, H3, EZHIP, or TERT mutations have been detected in a fraction of infratentorial ependymal tumors. Finally, MYCN amplifications have recently been identified in spinal ependymomas, in addition to the previously known mutations in NF2. This review summarizes how recent findings regarding biology, molecular tumor typing, and clinical outcome have impacted the classification of ependymomas as suggested by the updated 2021 WHO CNS tumor classification system. We focus on changes compared to the previous classification of 2016 and discuss how a formal grading could evolve in the future and guide clinicians to treat ependymoma patients.

Myxopapillary ependymomas; proximity to the conus and its effect on presentation and outcomes

Background:

Myxopapillary ependymomas (MPE) are intradural spinal tumors with a predilection to the filum terminale. Damage to conus medullaris during surgery can result in sphincteric and sexual dysfunction. The purpose of this study is to determine how myxopapillary ependymoma proximity to the conus impacts patient presentation, extent of resection, and clinical outcomes.

Methods:

Fifty-one patients who underwent surgical resection of pathologically confirmed myxopapillary ependymoma with at least 1 year of follow-up were included in the study. We collected initial presenting symptoms, distance of the tumor from the conus, extent of resection, and postoperative clinical outcomes including bladder dysfunction.

Results:

Average age was 38 years (range 7–75 years) with a male to female ratio of 1.43:1. Patients most commonly presented with pain symptoms (88%), and 12 patients (23.5%) had urologic symptoms on presentation. The mean tumor distance from the tip of the conus was 1.60 cm (10 cm above to 21 cm below the tip of the conus). Patients with tumors in contact with the conus had a significantly higher rate of preoperative urinary symptoms and were more likely (32% vs. 14%) to suffer postoperative urinary sphincteric disturbances. Tumors with direct invasion of the conus medullaris were more likely to require intralesional resection and fail to achieve a gross total resection (GTR).

Conclusion:

Patients with MPE in close proximity to the conus were more likely to suffer from long-term morbidity related to urologic issues following surgical resection. Adjuvant radiotherapy may be a viable option for patients who fail to achieve GTR.