Adult Spinal Ependymomas: An Epidemiologic Study

MYCN immunohistochemistry as surrogate marker for MYCN-amplified spinal ependymomas

MYCN (master regulator of cell cycle entry and proliferative metabolism) gene amplification defines a molecular subgroup of spinal cord ependymomas that show high-grade morphology and aggressive behavior. Demonstration of MYCN amplification by DNA methylation or fluorescence-in situ hybridization (FISH) is required for diagnosis. We aimed to (i) assess prevalence and clinicopathological features of MYCN-amplified spinal ependymomas and (ii) evaluate utility of immunohistochemistry (IHC) for MYCN protein as a surrogate for molecular testing. A combined retrospective-prospective study spanning 8 years was designed during which all spinal cord ependymomas with adequate tissue were subjected to MYCN FISH and MYCN IHC. Among 77 spinal cord ependymomas included, MYCN amplification was identified in 4 samples from 3 patients (3/74, 4%) including two (1st and 2nd recurrences) from the same patient. All patients were adults (median age at diagnosis of 32 years) including two females and one male. The index tumors were located in thoracic (n = 2) and lumbar (n = 1) spinal cord. One of the female patients had neurofibromatosis type 2 (NF2). All four tumors showed anaplastic histology. Diffuse expression of MYCN protein was seen in all four MYCN-amplified samples but in none of the non-amplified cases, thus showing 100% concordance with FISH results. On follow-up, the NF2 patient developed widespread spinal dissemination while another developed recurrence proximal to the site of previous excision. To conclude, MYCN-amplified spinal ependymomas are rare tumors, accounting for ~ 4% of spinal cord ependymomas. Within the limitation of small sample size, MYCN IHC showed excellent concordance with MYCN gene amplification.

Clinical presentation and extent of resection impacts progression-free survival in spinal ependymomas

PURPOSE

Primary treatment of spinal ependymomas involves surgical resection, however recurrence ranges between 50 and 70%. While the association of survival outcomes with lesion extent of resection (EOR) has been studied, existing analyses are limited by small samples and archaic data resulting in an inhomogeneous population. We investigated the relationship between EOR and survival outcomes, chiefly overall survival (OS) and progression-free survival (PFS), in a large contemporary cohort of spinal ependymoma patients.

METHODS

Adult patients diagnosed with a spinal ependymoma from 2006 to 2021 were identified from an institutional registry. Patients undergoing primary surgical resection at our institution, ≥ 1 routine follow-up MRI, and pathologic diagnosis of ependymoma were included. Records were reviewed for demographic information, EOR, lesion characteristics, and pre-/post-operative neurologic symptoms. EOR was divided into 2 classifications: gross total resection (GTR) and subtotal resection (STR). Log-rank test was used to compare OS and PFS between patient groups.

RESULTS

Sixty-nine patients satisfied inclusion criteria, with 79.7% benefitting from GTR. The population was 56.2% male with average age of 45.7 years, and median follow-up duration of 58 months. Cox multivariate model demonstrated significant improvement in PFS when a GTR was attained (p <.001). Independently ambulatory patients prior to surgery had superior PFS (p <.001) and OS (p =.05). In univariate analyses, patients with a syrinx had improved PFS (p =.03) and were more likely to benefit from GTR (p =.01). Alternatively, OS was not affected by EOR (p =.78).

CONCLUSIONS

In this large, contemporary series of adult spinal ependymoma patients, we demonstrated improvements in PFS when GTR was achieved.

Association Between Urbanicity and Outcomes Among Patients with Spinal Cord Ependymomas in the United States

BACKGROUND

Spinal cord ependymomas (SCEs) represent the most common intramedullary spinal cord tumors among adults. Research shows that access to neurosurgical care and patient outcomes can be greatly influenced by patient location. This study investigates the association between the outcomes of patients with SCE in metropolitan and nonmetropolitan areas.

METHODS

Cases of SCE between 2004 and 2019 were identified within the Central Brain Tumor Registry of the United States, a combined dataset including the Centers for Disease Control and Prevention's National Program of Cancer Registries and National Cancer Institute's Surveillance, Epidemiology, and End Results Program data. Multivariable logistic regression models were constructed to evaluate the association between urbanicity and SCE treatment, adjusted for age at diagnosis, sex, race and ethnicity. Survival data was available from 42 National Program of Cancer Registries (excluding Kansas and Minnesota, for which county data are unavailable), and Cox proportional hazard models were used to understand the effect of surgical treatment, county urbanicity, age at diagnosis, and the interaction effect between age at diagnosis and surgery, on the survival time of patients.

RESULTS

Overall, 7577 patients were identified, with 6454 (85%) residing in metropolitan and 1223 (15%) in nonmetropolitan counties. Metropolitan and nonmetropolitan counties had different age, sex, and race/ethnicity compositions; however, demographics were not associated with differences in the type of surgery received when stratified by urbanicity. Irrespective of metropolitan status, individuals who were American Indian/Alaska Native non-Hispanic and Hispanic (all races) were associated with reduced odds of receiving surgery. Individuals who were Black non-Hispanic and Hispanic were associated with increased odds of receiving comprehensive treatment. Diagnosis of SCE at later ages was linked with elevated mortality (hazard ratio = 4.85, P < 0.001). Gross total resection was associated with reduced risk of death (hazard ratio = 0.37, P = 0.004), and age did not interact with gross total resection to influence risk of death.

CONCLUSIONS

The relationship between patients' residential location and access to neurosurgical care is critical to ensuring equitable distribution of care. This study represents an important step in delineating areas of existing disparities.

MYCN amplification in spinal ependymoma: A five-year retrospective study

Spinal ependymoma with MYCN amplification is a newly recognized type of spinal ependymoma that is known to be associated with poor prognosis. Available studies on this relatively rare tumor type have observed that these tumors tend to disseminate along the spinal cord and behave aggressively with worse overall and progression-free survival compared to the other types of ependymoma. In this study, we describe the clinical and histopathological features of spinal ependymomas in a single institution cohort with emphasis on those with MYCN amplification.

Incidental Discovery of a Presacral Extradural Myxopapillary Ependymoma

Ependymoma is a malignant central nervous system tumor arising from the lining of the ventricles or central canal of the spinal cord. Extradural spinal ependymomas arise from heterotopic ependymal cells or the coccygeal medullary vestige and are extremely infrequent. We present a rare case of presacral extradural ependymoma. Extradural ependymomas typically demonstrate an extraneural spread and, thus, surveillance of the entire central nervous system is not typically recommended. A radiograph of the chest, liver profile, and attention to palpable lymphadenopathy (especially inguinal) on physical examination are vital for surveillance. Obtaining an R0 resection is the most important prognostic factor in survival and local recurrence.

Image-Guided Robotic Radiosurgery for the Management of Spinal Ependymomas

Background

Ependymomas are rare neoplasms of the central nervous system (CNS), usually localized intracranially and most commonly diagnosed in children. Spinal ependymomas are more frequent in young adults. They are either primary lesions or manifest as disseminated seeding of cranial tumors. Data on the management of spinal ependymoma lesions remain scarce, especially concerning stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT). The purpose of this study is to report the treatment outcomes of two institutions using robotic radiosurgery (RRS) for the treatment of spinal ependymomas.

Materials and Methods

All patients with a histopathologically confirmed diagnosis of an ependymoma WHO grade II or III who were treated with RRS for one or more spinal lesions were included in this analysis.

Results

Twelve patients underwent RRS for the treatment of 32 spinal ependymoma lesions between 2005 and 2020. Two patients were below the age of 18 when treated, whereas nine patients (75%) suffered from a primary spinal ependymoma. The median dose was 15 Gy prescribed to a median isodose of 70%, with 27 lesions (84%) receiving a single-session treatment. The local control (LC) after a median follow-up of 56.7 months was 84%. LC rates at 1, 3, and 5 years were 92, 85, and 77%, respectively. The Kaplan-Meier estimated overall survival after 1, 3, and 5 years were 75, 75, and 64%, respectively. Five patients died, all of them suffering from an anaplastic ependymoma, with widespread CNS tumor progression being the reason for death in four patients. The majority of patients (58%) showed a stable neurological status at the last available follow-up. Overall, the treatment was well tolerated.

Conclusion

RRS appears to be a safe and efficient treatment modality for managing primary and secondary spinal ependymal tumors in patients with multiple lesions and local recurrences.

Anaplastic Transformation in Myxopapillary Ependymoma: A Report of 2 Cases and Review of the Literature

Myxopapillary ependymoma (MPE) is a relatively common neoplasm arising primarily in the filum terminale/lumbosacral region of the spinal cord. It is designated as a grade I tumor in the most recent WHO Classification of Tumours of the CNS, although aggressive clinical behavior can be observed, especially in cases arising in an extradural location. Anaplastic transformation in MPE is exceedingly rare with <20 examples reported in the English literature, and consensus on diagnostic features and definitive grading remain to be determined. Here, we present 2 cases of recurrent MPE with anaplastic features, both of which had histology consistent with conventional MPE as well as areas with significant atypia, frequent mitotic figures, elevated Ki-67 proliferation indices (>10%-50%), necrosis, and focal vascular proliferation. Targeted next-generation sequencing panels revealed no definitive pathogenic mutations or fusion proteins in either case. Copy number profiling, methylation profiling, and t-Distributed Stochastic Neighbor Embedding were performed to investigate the molecular characteristics of these tumors. To the best of our knowledge, these are the first reported cases of MPE with anaplastic features with methylation profiling data. In addition, we review the literature and discuss common histologic and molecular findings associated with anaplastic features in MPE.

Fatal holocord recurrence of a pregnancy-related, low-grade spinal ependymoma: case report and review of an unusual clinical phenomenon

INTRODUCTION

Pregnancy-related spinal tumors (PRSTs) are unusual tumors that present during pregnancy or within a year after delivery. We describe a fatal holocord recurrence of a spinal ependymoma, which, to the best of our knowledge, is one of the most extensive PRSTs reported thus far.

CASE PRESENTATION

A 21-year-old primigravida presented at 6 months of gestation with urinary incontinence for 2 months and spastic paraparesis for 1 month. MRI showed a conus intramedullary lesion from T10 to 12. Near-total resection of the lesion was performed. The histopathological diagnosis was that of a cellular ependymoma (WHO grade II). The patient presented 6 months later with progressive quadriparesis and breathing difficulty. MRI demonstrated holocord recurrence of the tumor with edema extending to the pontomedullary junction. The patient succumbed to respiratory failure before decompression of the tumor could be performed.

DISCUSSION

This case highlights an unusual clinical course of a pregnancy-related, low-grade spinal ependymoma. The possible hormonal and genetic mechanisms underlying the aggressive involvement of the entire spinal cord by the recurrent tumor are discussed in the light of a literature review. Future studies may shed light on the possibility of utilizing these mechanisms as therapeutic targets to alter the clinical course of aggressive spinal ependymomas.

Ependymoma, NOS and anaplastic ependymoma incidence and survival in the United States varies widely by patient and clinical characteristics, 2000-2016

BACKGROUND

Ependymoma is a rare CNS tumor arising from the ependymal lining of the ventricular system. General differences in incidence and survival have been noted but not examined on a comprehensive scale for all ages and by histology. Despite the rarity of ependymomas, morbidity/mortality associated with an ependymoma diagnosis justifies closer examination.

METHODS

Incidence data were obtained from the Central Brain Tumor Registry of the United States in collaboration with the Centers for Disease Control and Prevention and the National Cancer Institute, and survival data from Surveillance Epidemiology and End Results, from 2000 to 2016 for anaplastic ependymoma and ependymoma, not otherwise specified (NOS). Age-adjusted incidence rates (IRs) per 100 000 person-years were analyzed by age, sex, race, and location. Survival analysis was performed with Kaplan-Meier curves and multivariable Cox proportional hazards models.

RESULTS

Incidence of anaplastic ependymoma was highest in ages 0 to 4 years. African American populations had lower incidence but had a 78% increased risk of death compared to white populations (hazard ratio [HR]: 1.78 [95% CI, 1.30-2.44]). Incidence was highest for anaplastic ependymoma in the supratentorial region. Adults (age 40+ years) had almost twice the risk of death compared to children (ages 0-14 years) (HR: 1.97 [95% CI, 1.45-2.66]). For ependymoma, NOS, subtotal resection had a risk of mortality 1.86 times greater than gross total resection ([HR: 1.86 [95% CI, 1.32-2.63]).

CONCLUSIONS

African American populations experienced higher mortality rates despite lower incidence compared to white populations. Extent of resection is an important prognostic factor for survival. This highlights need for further evaluation of treatment patterns and racial disparities in the care of patients with ependymoma subtypes.

Spinal Cord Ependymomas With MYCN Amplification Show Aggressive Clinical Behavior

Adult spinal cord ependymomas are typically low grade and have a relatively favorable clinical course following gross total resection. We report 4 cases of anaplastic spinal cord ependymoma with MYCN amplification, an exceptionally rare finding. All cases occurred in the spinal cord of adolescent and young adult women and had morphological and immunohistochemical features of anaplastic ependymomas (World Health Organization grade III). Chromosomal microarray analysis demonstrated amplification of 2p24 (including MYCN) in all cases. One patient died 6 months after surgery. Another patient recently had removal of metastatic nodules in the thoracic region, following gross total resection and adjuvant radiation therapy of a lumbar ependymoma 1 year previously. One patient responded well after chemotherapy but died after multiple relapses 82 months after diagnosis. We found MYCN amplification reported in 2 other ependymomas, both anaplastic and arising in the spinal cord of adult females (Brain Pathol 2001;11:133-43). One patient had multiple recurrences in the spinal cord and an intracranial metastasis. Although MYCN amplification is rare in ependymomas, the current and previously reported cases suggest that this is associated with higher-grade histology, spinal location, and often unfavorable prognosis. The clinical significance and therapeutic implications of MYCN amplification in ependymomas require further evaluation.

Comparison of epidemiology, treatments, and outcomes in pediatric versus adult ependymoma

Background

Mounting evidence supports the presence of heterogeneity in the presentation of ependymoma patients with respect to location, histopathology, and behavior between pediatric and adult patients. However, the influence of age on treatment outcomes in ependymoma remains obscure.

Methods

The SEER database years 1975–2016 were queried. Patients with a diagnosis of ependymoma were identified using the International Classification of Diseases for Oncology, Third Edition, coding system. Patients were classified into one of 4 age groups: children (age 0–12 years), adolescents (age 13–21 years), young adults (age 22–45 years), and older adults (age >45 years). The weighed multivariate analysis assessed the impact of age on survival outcomes following surgical treatment.

Results

There were a total of 6076 patients identified with ependymoma, of which 1111 (18%) were children, 529 (9%) were adolescents, 2039 (34%) were young adults, and 2397 (40%) were older adults. There were statistically significant differences between cohorts with respect to race (P < .001), anatomical location (P < .001), extent of resection (P < .001), radiation use (P < .001), tumor grade (P < .001), histological classification (P < .001), and all-cause mortality (P < .001). There was no significant difference between cohorts with respect to gender (P = .103). On multivariate logistic regression, factors associated with all-cause mortality rates included males (vs females), supratentorial location (vs spinal cord tumors), and radiation treatment (vs no radiation).

Conclusions

Our study using the SEER database demonstrates the various demographic and treatment risk factors that are associated with increased rates of all-cause mortality between the pediatric and adult populations following a diagnosis of ependymoma.

MYCN amplification drives an aggressive form of spinal ependymoma

Spinal ependymal tumors form a histologically and molecularly heterogeneous group of tumors with generally good prognosis. However, their treatment can be challenging if infiltration of the spinal cord or dissemination throughout the central nervous system (CNS) occurs and, in these cases, clinical outcome remains poor. Here, we describe a new and relatively rare subgroup of spinal ependymal tumors identified using DNA methylation profiling that is distinct from other molecular subgroups of ependymoma. Copy number variation plots derived from DNA methylation arrays showed MYCN amplification as a characteristic genetic alteration in all cases of our cohort (n = 13), which was subsequently validated using fluorescence in situ hybridization. The histological diagnosis was anaplastic ependymoma (WHO Grade III) in ten cases and classic ependymoma (WHO Grade II) in three cases. Histological re-evaluation in five primary tumors and seven relapses showed characteristic histological features of ependymoma, namely pseudorosettes, GFAP- and EMA positivity. Electron microscopy revealed cilia, complex intercellular junctions and intermediate filaments in a representative sample. Taking these findings into account, we suggest to designate this molecular subgroup spinal ependymoma with MYCN amplification, SP-EPN-MYCN. SP-EPN-MYCN tumors showed distinct growth patterns with intradural, extramedullary localization mostly within the thoracic and cervical spine, diffuse leptomeningeal spread throughout the whole CNS and infiltrative invasion of the spinal cord. Dissemination was observed in 100% of cases. Despite high-intensity treatment, SP-EPN-MYCN showed significantly worse median progression free survival (PFS) (17 months) and median overall survival (OS) (87 months) than all other previously described molecular spinal ependymoma subgroups. OS and PFS were similar to supratentorial ependymoma with RELA-fusion (ST-EPN-RELA) and posterior fossa ependymoma A (PF-EPN-A), further highlighting the aggressiveness of this distinct new subgroup. We, therefore, propose to establish SP-EPN-MYCN as a new molecular subgroup in ependymoma and advocate for testing newly diagnosed spinal ependymal tumors for MYCN amplification.

Molecular foundations of primary spinal tumors-implications for surgical management

Primary spinal tumors are rare lesions that require careful clinical management due to their intimate relationship with critical neurovascular structures and the significant associated risk of morbidity. While the advent of molecular and genomic profiling is beginning to impact the management of the cranial counterparts, translation for spinal tumors has lagged behind. Maximal safe surgical resection remains the mainstay of patients with primary spinal tumors, with extent of resection and histology the only consistently identified independent predictors of survival. Adjuvant therapy has had limited impact. To develop targeted neoadjuvant and adjuvant therapies, improve prognostication, and enhance patient selection in spinal oncology, a thorough understanding of the current molecular and genomic landscape of spinal tumors is required. In this review, we detail the epidemiology, current standard-of-care, and molecular features of the most commonly encountered intramedullary spinal cord tumors (IMSCT), intradural extramedullary (IDEM) tumors, and primary spinal column malignancies (PSCM). We further discuss current efforts and future opportunities for integrating molecular advances in spinal oncology with clinical management.

National Patterns of Care in the Management of World Health Organization Grade II and III Spinal Ependymomas

BACKGROUND

Spinal ependymomas are rare, with an incidence of 1 per 100,000. Given the paucity of data for higher grade II and III disease, the management and patterns of care require further investigation.

METHODS

Our study of 1345 patients with higher-grade spinal ependymoma used χ² tests and simple and multivariable logistic regression models to assess demographic and clinical factors associated with therapy. Kaplan-Meier and log-rank tests were used to assess overall survival (OS).

RESULTS

Most grade II patients received surgery alone (81.1%) compared with 36.8% of grade III. Approximately 60% of patients with grade III ependymomas received radiotherapy (RT) versus 15.3% of grade II (P < 0.001). Patients living ≤32 km (20 miles) from a facility were more likely to receive RT (P < 0.001) than were those living further away. On multivariable logistic regression, grade (grade III, odds ratio, 8.6; P < 0.001) and facility distance were significantly associated with receipt of RT (P < 0.0001). The 5-year and 10-year OS was 94.7%/85.1% for patients with grade II disease and 58.2%/46.4% for grade III disease (P < 0.0001). OS was highest at facilities treating an average of 15 patients over 10 years, corresponding to the top 81st percentile in volume. The 10-year OS was 92.6% at facilities treating at least 15 patients and 88.0% at facilities treating 6-14 patients.

CONCLUSIONS

Approximately 40% of patients with grade III ependymomas do not receive immediate adjuvant therapy, which may be related to distance from a facility. Patients with this rare tumor may benefit from multidisciplinary care at facilities with a larger volume.