Intracranial Subependymoma: A SEER Analysis 2004–2013

Pediatric CNS tumors and 2021 WHO classification: what do oncologists need from pathologists?

The fifth edition of the WHO Classification of Tumors of the Central Nervous System (CNS), published in 2021, established new approaches to both CNS tumor nomenclature and grading, emphasizing the importance of integrated diagnoses and layered reports. This edition increased the role of molecular diagnostics in CNS tumor classification while still relying on other established approaches such as histology and immunohistochemistry. Moreover, it introduced new tumor types and subtypes based on novel diagnostic technologies such as DNA methylome profiling. Over the past decade, molecular techniques identified numerous key genetic alterations in CSN tumors, with important implications regarding the understanding of pathogenesis but also for prognosis and the development and application of effective molecularly targeted therapies. This review summarizes the major changes in the 2021 fifth edition classification of pediatric CNS tumors, highlighting for each entity the molecular alterations and other information that are relevant for diagnostic, prognostic, or therapeutic purposes and that patients' and oncologists' need from a pathology report.

Intraventricular Subependymoma With Obstructive Hydrocephalus: A Case Report and Literature Review

Subependymomas are benign tumors of the ventricles that grow from the ventricular wall into the cerebrospinal fluid spaces within the brain, obstructing the flow of the cerebrospinal fluid and causing obstructive hydrocephalus. It is estimated that ependymomas represent between 0.2% and 0.7% of all intracranial tumors. They arise most frequently in the fourth ventricle (50-60%) and the lateral ventricles (30-40%). We present the case of a 50-year-old patient, previously diagnosed with an intraventricular process, admitted in our clinic. At neurological examination, the patient was cooperative, bradylalic, and bradypsychic, with right hemiparesis, postural and balance disorders, and occasionally sphincteric incontinence. MRI with contrast described a left intraventricular tumor, in the frontal horn of the left lateral ventricle with homogeneous appearance, with a maximum diameter of 50 mm and base of insertion at the adjacent ependyma of the foramen of Monro, which determined obstructive hydrocephalus. Total resection of the left intraventricular cerebral tumor was achieved. Histopathological analysis revealed a subependymoma. Postoperative recovery was slowly favorable, with significant neurological improvement. At neurological examination at three-month follow-up, the patient's right hemiparesis and unsystematized balance disorders improved. A contrast-enhanced CT scan was performed, highlighting left frontal sequelae hypodensity corresponding to the operated tumor, enlarged left lateral ventricle without active hydrocephalus, and no sign of tumor recurrence. At six-month follow-up, clinico-radiologic findings coincide with those from three-month follow-up. Subependymomas are slow-growing (grade 1) tumors and generally have a favorable prognosis. Unfortunately, due to their anatomical level, multiple complications can arise, caused from obstructive hydrocephalus complications, such as cognitive dysfunction and incontinence. Tumor resection should be complete, a successful operation being a challenge for every neurosurgeon.

Disappearance of a Ruptured Feeding Artery Fusiform Aneurysm After the Resection of a Large Subependymoma: A Case Report

Aneurysm formation on the tumor-feeding artery is rare, and its treatment strategies are not yet settled. We herein report the case of a 49-year-old female with a large subependymoma in the left lateral ventricle presenting remote intracerebral hemorrhage at the left posterior cingulate gyrus. Digital subtraction angiography (DSA) revealed the presence of a 5.5 mm fusiform tumor-feeding artery aneurysm on the left parieto-occipital branch of the posterior cerebral artery, considered to be the source of the hemorrhage. Three months after total tumor resection, the aneurysm subsequently disappeared on the follow-up angiography. Subependymomas are generally known as tumors with low vascularity and seldom present with symptoms such as intracerebral hemorrhage. From the subsequent disappearance of the aneurysm after the complete tumor resection, the pathophysiological cause of the aneurysm formation is assumed to be flow-related hemodynamic vessel wall stress of the feeding artery. Tumor resection alone may be a favorable first treatment strategy to avoid unnecessary brain damage since subsequent disappearance of the aneurysm can be expected. The coexistence of feeding artery aneurysms should be kept in mind, especially in cases with remote hemorrhage.

Latest classification of ependymoma in the molecular era and advances in its treatment: a review

Ependymoma is a rare central nervous system (CNS) tumour occurring in all age groups and is one of the most common paediatric malignant brain tumours. Unlike other malignant brain tumours, ependymomas have few identified point mutations and genetic and epigenetic features. With advances in molecular understanding, the latest 2021 World Health Organization (WHO) classification of CNS tumours divided ependymomas into 10 diagnostic categories based on the histology, molecular information and location; this accurately reflected the prognosis and biology of this tumour. Although maximal surgical resection followed by radiotherapy is considered the standard treatment method, and chemotherapy is considered ineffective, the validation of the role of these treatment modalities continues. Although the rarity and long-term clinical course of ependymoma make designing and conducting prospective clinical trials challenging, knowledge is steadily accumulating and progress is being made. Much of the clinical knowledge obtained from clinical trials to date was based on the previous histology-based WHO classifications, and the addition of new molecular information may lead to more complex treatment strategies. Therefore, this review presents the latest findings on the molecular classification of ependymomas and advances in its treatment.

Third Ventricular Subependymomas: Clinical Features and Outcomes Over Two Decades

BACKGROUND

Subependymomas are uncommon, benign slow-growing neoplasms of the central nervous system preferentially arising within the fourth and lateral ventricles. Third ventricle involvement has been described rarely. The aim of this study is to provide the first systematic review of third ventricular subependymomas (TVSE) by analyzing all reported cases over 2 decades and describing a case example.

METHODS

MEDLINE and Embase databases were searched for the 20 years ending January 1, 2022, using relevant MeSH and non-MeSH terms, including "subependymoma" and "third ventricle." Methodology followed PRISMA guidelines.

RESULTS

Of 804 identified studies, 131 met inclusion eligibility. The literature yielded 17 patients with TVSE plus our example (18 total). Of these patients, 83% (15/18) presented in adulthood (average age, 42 ± 19 years), of whom 73% were women. The pediatric cohort age was 5 ± 1 years, 67% (4/6) of whom were girls. The most common presenting symptom in both cohorts was headache (80%), followed by memory disturbances and vomitus. In adults, symptomatic tumors were approached by open craniotomy in all but 1 case, most using a transcallosal approach. Gross total resection was obtained in 73%. A ventriculoperitoneal shunt was inserted in 2/15 adult and 4/6 pediatric patients. Overall, both cohorts showed symptomatic improvement without disease recurrence. One patient died perioperatively.

CONCLUSIONS

Subependymomas should be considered in the differential diagnosis of third ventricular tumors. The clinical presentation of TVSE mainly parallels hydrocephalus symptoms and, hence, awareness is of vital importance for timely treatment. The surgical goal should be gross total resection, which can be curative and offers greatest clinical improvement across the population.

Coexistence of Two Distinct Tumor Types Within One Posterior Fossa Mass Lesion in an Adult Patient Verified by DNA-Methylation Analysis: A Case Report

We report an 81-year-old patient who underwent microsurgical resection of a posterior fossa mass lesion. Intraoperative findings were suggestive of the presence of two distinctly different tumor types within the lesion, one of which was well-circumscribed and avascular, whereas the other one showed an adhesive growth pattern and extensive vascularisation. Histopathological analysis, including deoxyribonucleic acid (DNA)-methylation-based classification, substantiated the intraoperative impression and confirmed the presence of a subependymoma central nervous system (CNS) World Health Organization (WHO) grade 1 as well as the presence of a hemangioblastoma CNS WHO grade 1. To our knowledge, our patient represents only the second reported case of such a rare constellation. Even though DNA-methylation-based classification is not yet required for the classification of all CNS tumor types by the 2021 WHO classification of tumors of the CNS, it proved to be crucial to verify the final diagnosis in our patient. In the future, DNA-methylation analysis will most likely become an important asset in neuro-oncological diagnostics and further help to guide treatment strategies in complex or rare clinical cases.

A Case of Cerebellar Intraparenchymal Subependymoma with Next-Generation Sequencing Analysis

Subependymomas are rare, intraventricular glial tumors histologically characterized by clusters of small uniform cells distributed in an abundant fibrillary matrix. These tumors can arise in the parenchyma of the cerebrum, cerebellum, or spinal cord. Herein, we report an extremely rare case of cerebellar intraparenchymal subependymoma in a 62-year-old woman. The patient presented with dizziness for several years, and brain magnetic resonance imaging revealed a well-defined solid mass in the right cerebellum, upon which a stereotactic biopsy was performed. Histologically, the tumor showed a distinctive multinodular pattern with unevenly distributed glial cells and an abundant fibrillary matrix. Next-generation sequencing analysis showed balanced genomes without genetic alterations, including single-nucleotide variants, small insertions, deletions, or copy number alterations. Follow-up magnetic resonance imaging revealed that the size of the mass has not changed; the patient has not received any surgical treatments since the pathologic diagnosis and is living healthily.

Exploration of the prognostic value of the resection of adult brainstem high-grade glioma based on competing risk model, propensity score matching, and conditional survival rate

BACKGROUND

Adult brainstem high-grade glioma (HGG) is a refractory disease, and the treatment strategy of resection is still controversial.

OBJECTIVE

To investigate the prognostic value of brainstem HGG resection in adults.

METHODS

We collected 126,386 samples from the Surveillance, Epidemiology, and End Results (SEER) database between 1998 and 2016, and screened 973 patients diagnosed with adult brainstem HGG, who were in turn, grouped into 899 cases of non-resections and 74 cases of resections. Competing risk models were used to screen independent prognostic factors. Propensity score matching (PSM) was performed to reduce the influence of confounding factors. Conditional survival (CS) rate was considered to evaluate the changes in overall survival (OS) and disease-specific survival (DSS) of patients with HGG over time.

RESULTS

Based on the competing risk model and PSM, univariate analysis showed that age ≥ 45 years and male gender were poor prognostic factors for adult brainstem HGG. No previous history of glioma was a beneficial factor. Multivariate analysis revealed only the absence of a history of glioma to be a favorable prognostic factor. Considering the CS rate of the resection group, after the patient had survived for 3 years, the OS and DSS remained unchanged at 100% during the fourth and fifth years, whereas in the non-resection group, the OS and DSS of the patients were 82% and 74%, respectively.

CONCLUSION

Adult brainstem HGG resection has a poor prognosis in the early stage; however, patients have a potentially significant survival benefit after 3 years of survival.

Benign Glioma

Benign glioma broadly refers to a heterogeneous group of slow-growing glial tumors with low proliferative rates and a more indolent clinical course. These tumors may also be described as "low-grade" glioma (LGG) and are classified as WHO grade I or II lesions according to the Classification of Tumors of the Central Nervous System (CNS) (Louis et al. in Acta Neuropathol 114:97-109, 2007). Advances in molecular genetics have improved understanding of glioma tumorigenesis, leading to the identification of common mutation profiles with significant treatment and prognostic implications. The most recent WHO 2016 classification system has introduced several notable changes in the way that gliomas are diagnosed, with a new emphasis on molecular features as key factors in differentiation (Wesseling and Capper in Neuropathol Appl Neurobiol 44:139-150, 2018). Benign gliomas have a predilection for younger patients and are among the most frequently diagnosed tumors in children and young adults (Ostrom et al. in Neuro Oncol 22:iv1-iv96, 2020). These tumors can be separated into two clinically distinct subgroups. The first group is of focal, well-circumscribed lesions that notably are not associated with an increased risk of malignant transformation. Primarily diagnosed in pediatric patients, these WHO grade I tumors may be cured with surgical resection alone (Sturm et al. in J Clin Oncol 35:2370-2377, 2017). Recurrence rates are low, and the prognosis for these patients is excellent (Ostrom et al. in Neuro Oncol 22:iv1-iv96, 2020). Diffuse gliomas are WHO grade II lesions with a more infiltrative pattern of growth and high propensity for recurrence. These tumors are primarily diagnosed in young adult patients, and classically present with seizures (Pallud et al. Brain 137:449-462, 2014). The term "benign" is a misnomer in many cases, as the natural history of these tumors is with malignant transformation and recurrence as grade III or grade IV tumors (Jooma et al. in J Neurosurg 14:356-363, 2019). For all LGG, surgery with maximal safe resection is the treatment of choice for both primary and recurrent tumors. The goal of surgery should be for gross total resection (GTR), as complete tumor removal is associated with higher rates of tumor control and seizure freedom. Chemotherapy and radiation therapy (RT), while not typically a component of first-line treatment in most cases, may be employed as adjunctive therapy in high-risk or recurrent tumors and in some select cases. The prognosis of benign gliomas varies widely; non-infiltrative tumor subtypes generally have an excellent prognosis, while diffusely infiltrative tumors, although slow-growing, are eventually fatal (Sturm et al. in J Clin Oncol 35:2370-2377, 2017). This chapter reviews the shared and unique individual features of the benign glioma including diffuse glioma, pilocytic astrocytoma and pilomyxoid astrocytoma (PMA), subependymal giant cell astrocytoma (SEGA), pleomorphic xanthoastrocytoma (PXA), subependymoma (SE), angiocentric glioma (AG), and chordoid glioma (CG). Also discussed is ganglioglioma (GG), a mixed neuronal-glial tumor that represents a notable diagnosis in the differential for other LGG (Wesseling and Capper 2018). Ependymomas of the brain and spinal cord, including major histologic subtypes, are discussed in other chapters.

Clinical features and surgical outcomes of intracranial and spinal cord subependymomas

OBJECTIVE

Subependymomas are low-grade ependymal tumors whose clinical characteristics, radiographic features, and postsurgical outcomes are incompletely characterized due to their rarity. The authors present an institutional case series and a systematic literature review to achieve a better understanding of subependymomas.

METHODS

Adult patients with histologically confirmed subependymoma or mixed subependymoma-ependymoma surgically treated at a tertiary hospital between 1992 and 2020 were identified. A systematic literature review of the PubMed, Embase, Web of Science, and Google Scholar databases from inception until December 4, 2020, was conducted according to PRISMA guidelines. Data extracted from both groups included demographics, radiographic features, tumor characteristics, management, and follow-up variables.

RESULTS

Forty-eight unique patients with subependymoma were identified by chart review; of these patients, 8 (16.7%) had mixed subependymoma-ependymoma tumors. The median age at diagnosis was 49 years (IQR 19.8 years), and 26 patients (54.2%) were male. Forty-two patients (87.5%) had intracranial subependymomas, and 6 (12.5%) had spinal tumors. The most common presentation was headache (n = 20, 41.7%), although a significant number of tumors were diagnosed incidentally (n = 16, 33.3%). Among the 42 patients with intracranial tumors, 15 (35.7%) had hydrocephalus, and the most common surgical strategy was a suboccipital approach with or without C1 laminectomy (n = 26, 61.9%). Gross-total resection (GTR) was achieved in 33 cases (68.7%), and 2 patients underwent adjuvant radiotherapy. Most patients had no major postsurgical complications (n = 34, 70.8%), and only 1 (2.1%) had recurrence after GTR. Of 2036 reports initially identified in the systematic review, 39 were eligible for inclusion, comprising 477 patients. Of 462 patients for whom tumor location was reported, 406 (87.9%) were intracranial, with the lateral ventricle as the most common location (n = 214, 46.3%). Spinal subependymomas occurred in 53 patients (11.5%), with 3 cases (0.6%) in multiple locations. Similar to the case series at the authors' institution, headache was the most common presenting symptom (n = 231, 54.0%) among the 428 patients whose presentation was reported. Twenty-seven patients (6.3%) were diagnosed incidentally, and 36 cases (8.4%) were found at autopsy. Extent of resection was reported for 350 patients, and GTR was achieved in 250 (71.4%). Fifteen of 337 patients (4.5%) had recurrence or progression.

CONCLUSIONS

The authors' case series and literature review demonstrate that patients with subependymoma are well managed with resection and generally have a favorable prognosis.

Clinical independent prognostic factors and overall survival prognostic nomogram for intracranial subependymoma: A SEER population-based analysis 2004–2016

Purpose

This study was launched to ascertain the independent prognostic factors influencing the overall survival (OS) prognosis of intracranial subependymoma and construct a prognostic model to predict OS time.

Materials and methods

We collected data from patients with intracranial subependymoma, including treatment data, follow-up data, and clinical and pathological characteristics from the SEER database within 2004 to 2016, and patients were randomly classified into training and validation cohorts. Univariate and multivariate analyses were applied to the training group through building a Cox proportional hazards model. According to the results of multivariate analysis, we established a nomogram to forecast the OS rate of the per-case patient graphically, then calculated the accuracy of verification in both training and validation cohorts by concordance index (C-index). Univariate and multivariate analyses were used for different subgroups of unoperated versus operated, gross total resection (GTR), subtotal resection (STR), and biopsy after using the propensity score matching (PSM) analyses.

Results

A total of 667 patients were enrolled, and we randomly assigned 535 patients (80.21%) into the training cohort and 132 patients (19.79%) into the validation cohort. Age [hazard ratio (HR) = 6.355; 95% confidence interval (CI), 2.240–18.029; p = 0.001] and sex (HR = 0.475; 95% CI, 0.232–0.974; p = 0.042) were the independent prognostic factors in the training cohort. On the basis of age and sex, the nomogram was established to predict the OS for every patient (C-index = 0.733 ± 0.065 in the training cohort and 0.850 ± 0.065 in the validation cohort), and calibration plots reflected the reliability of the nomogram. Age, gender, or laterality was the independent prognostic factor for OS in the different matched subgroups of unoperated versus operated, GTR, STR, and biopsy. Surgical treatment, race, year of diagnosis, insurance, tumor location, tumor size, pathology, tumor grade, and radiation were not statistically significantly different in OS for subependymoma in our research.

Conclusion

Age and sex were the independent prognostic variables for OS in intracranial subependymoma. According to our research, we should not be more inclined to choose conservative or surgical treatment. Nonetheless, the information that we present might be useful to suggest potential hypotheses to be tested in the clinical research setting.

Imaging characteristics of 4th ventricle subependymoma

PURPOSE

Subependymomas located within the 4th ventricle are rare, and the literature describing imaging characteristics is sparse. Here, we describe the clinical and radiological characteristics of 29 patients with 4th ventricle subependymoma.

METHODS

This is a retrospective multi-center study performed after Institutional Review Board (IRB) approval. Patients diagnosed with suspected 4th ventricle subependymoma were identified. A review of clinical, radiology, and pathology reports along with magnetic resonance imaging (MRI) images was performed.

RESULTS

Twenty-nine patients, including 6 females, were identified. Eighteen patients underwent surgery with histopathological confirmation of subependymoma. The median age at diagnosis was 52 years. Median tumor volume for the operative cohort was 9.87 cm³, while for the non-operative cohort, it was 0.96 cm³. Thirteen patients in the operative group exhibited symptoms at diagnosis. For the total cohort, the majority of subependymomas (n = 22) were isointense on T1, hyperintense (n = 22) on T2, and enhanced (n = 24). All tumors were located just below the body of the 4th ventricle, terminating near the level of the obex. Fourteen cases demonstrated extension of tumor into foramen of Magendie or Luschka.

CONCLUSION

To the best of our knowledge, this is the largest collection of 4th ventricular subependymomas with imaging findings reported to date. All patients in this cohort had tumors originating between the bottom of the body of the 4th ventricle and the obex. This uniform and specific site of origin aids with imaging diagnosis and may infer possible theories of origin.

Molecular Classification and Therapeutic Targets in Ependymoma

Ependymoma is a biologically diverse tumor wherein molecular classification has superseded traditional histological grading based on its superior ability to characterize behavior, prognosis, and possible targeted therapies. The current, updated molecular classification of ependymoma consists of ten distinct subgroups spread evenly among the spinal, infratentorial, and supratentorial compartments, each with its own distinct clinical and molecular characteristics. In this review, the history, histopathology, standard of care, prognosis, oncogenic drivers, and hypothesized molecular targets for all subgroups of ependymoma are explored. This review emphasizes that despite the varied behavior of the ependymoma subgroups, it remains clear that research must be performed to further elucidate molecular targets for these tumors. Although not all ependymoma subgroups are oncologically aggressive, development of targeted therapies is essential, particularly for cases where surgical resection is not an option without causing significant morbidity. The development of molecular therapies must rely on building upon our current understanding of ependymoma oncogenesis, as well as cultivating transfer of knowledge based on malignancies with similar genomic alterations.

Tumor characteristics and surgical outcomes of intracranial subependymomas: a systematic review and meta-analysis

OBJECTIVE

The tumor characteristics and surgical outcomes of intracranial subependymomas are poorly defined. In this study the authors aimed to provide a comprehensive review of all clinical, pathological, radiological, and surgical aspects of this important neoplasm to inform future management strategies.

METHODS

A systematic review and meta-analysis of MEDLINE, EMBASE, Cochrane, and Google Scholar databases adherent to PRISMA guidelines was conducted.

RESULTS

Of the 1145 articles initially retrieved, 24 studies encompassing 890 cases were included. The authors identified 3 retrospective cohort studies and 21 case series, but no controlled trials. Mean age at presentation was 46.7 ± 18.1 years with a male predominance (70.2%). Common sites of tumor origin were the lateral ventricle (44.5%) and fourth ventricle (43.1%). Cumulative postoperative mortality and morbidity rates were 3.4% and 24.3% respectively. Meta-analysis revealed that male sex (HR 3.15, 95% CI 1.39-7.14, p = 0.006) was associated with poorer 5-year overall mortality rates. All-cause mortality rates were similar when performing subgroup meta-analyses for age (HR 0.50, 95% CI 0.03-7.36, p = 0.61), smaller subependymoma size (HR 1.51, 95% CI 0.78-2.92, p = 0.22), gross-total resection (HR 0.65, 95% CI 0.35-1.23, p = 0.18), and receipt of postoperative radiation therapy (HR 0.88, 95% CI 0.27-2.88, p = 0.84). Postoperative Karnofsky Performance Index scores improved by a mean difference of 1.62 ± 12.14 points (p = 0.42). The pooled overall 5-year survival rate was 89.2%, while the cumulative recurrence rate was 1.3% over a median follow-up ranging from 15.3 to 120.0 months. The pure subependymoma histopathological subtype was most prevalent (85.6%), followed by the mixed subependymoma-ependymoma tumor variant (13.7%).

CONCLUSIONS

Surgical extirpation without postoperative radiotherapy results in excellent postoperative survival and functional outcomes in the treatment of intracranial subependymomas. Aggressive tumor behavior should prompt histological reevaluation for a mixed subependymoma-ependymoma subtype. Further high-quality controlled trials are still required to investigate this rare tumor.

Intraparenchymal subependymoma: Case report and literature review

Background:

Intracranial subependymomas are rare slow-growing benign tumors typically located in the ventricular system, accounting for 0.07–0.7% of all intracranial neoplasms. Intraparenchymal subependymoma is extremely rare lesions, imposing a challenging diagnosis and management.

Case Description:

We describe a case of a supratentorial intraparenchymal mass on left occipital lobe in a 26-year-old woman with progressive headache and visual impairment. Differential diagnosis mainly included gliomas, neuronal-glial tumors, ependymoma, and subependymoma. Complete surgical resection was performed and histopathology analysis confirmed diagnosis of subependymoma. Despite its benign behavior the Ki67/MIB-1 labeling index assessed by immunohistochemistry was 5%. After 1 year of follow-up she was free of tumor recurrence.

Conclusion:

Intraparenchymal subependymoma is extremely rare tumors and literature review showed only 11 cases reported. In general, they are misdiagnosed as other tumors, so careful attention on clinical and radiological features must be taken when looking at a tumor close to the ventricular system, even though it does not have any obvious direct connection to it. Despite its benign nature, total removal must be attempted given that there are reports of recurrence, especially in partially removed tumors with high proliferation index. The role of adjuvant therapy is still limited and new treatment options are being developed as our knowledge on biological and molecular characteristics advances.

A rare case of intraparenchymal subependymoma in a child

Subependymoma is a slow-growing, exophytic, intraventricular glial neoplasm that commonly arises in the ventricular system. However, a report found that the frequency of intracerebral subependymoma was 0.4% in 1000 routine autopsies. To the best of our knowledge, only seven cases of intracerebral subependymoma have been reported. We report a rare case of intracerebral subependymoma in a child. An 11-year-old girl with generalized tonic-clonic seizures visited the emergency room and had an intraparenchymal tumor on the left frontal lobe on magnetic resonance imaging (MRI). Craniotomy with gross total removal was performed without any perioperative morbidities. The tumor was finally histopathologically diagnosed as a subependymoma.

Primary central nervous system T-cell lymphoma: An analysis from the surveillance, epidemiology, and end results program

BACKGROUND

Primary central nervous system T-cell lymphoma (PCNSTCL) is a rare neoplasm with few data regarding its common features and survival characteristics.

OBJECTIVE

To explore the Surveillance, Epidemiology, and End Results 18 (SEER 18) database to determine the epidemiology of PCNSTCL.

METHODS

The SEER 18 registry database was queried to identify patients diagnosed with PCNSTCL from 1973 to 2014 and extract their information. Age-specific rates and Kaplan-Meier overall survival (OS) were calculated. A Cox proportional hazards model was applied to investigate relationships between various demographic/treatment variables and OS.

RESULTS

The age-specific incidence rates were higher in the older population (≥60 years). Among 59 PCNSTCL cases from the SEER 18, the mean age at presentation was 55.8 years (SD, ±17.95), with a male predominance (1.36:1.00). The median follow-up was 8 months, and the median OS was 8 months (SE, ±4.162). The 1-, 3-, and 5-year OS was 46.3% [95% CI, 33.4%-59.2%], 32.8% [20.3%-45.3%], and 32.8% [20.3%-45.3%], respectively. Seventeen of the 59 patients survived at last follow-up. Patients < 60 years had a greater 3-year OS compared with patients ≥ 60 years (52.6% [33.6%-71.6%] vs 13.9% [1.4%-26.4%]. Multivariate analysis has demonstrated that only age at diagnosis (≥60/<60 years) exhibited a significant relationship with OS (HR, 3.495 [1.688-7.235];p = 0.001). Sex (female/male) was observed to have a doubted trend towards significance (HR, 0.487 [0.231-1.030]; p = 0.060).

CONCLUSIONS

PCNSTCL is generally of poor prognosis but younger age at diagnosis (<60 years) predicts a better prognosis.

The Effects of Surgery and Adjuvant Therapy on Survival Outcomes in Clear Cell Ependymomas: A Systematic Review and Meta-Analysis of Individual Patient Data

BACKGROUND

The survival outcomes of clear cell ependymomas are poorly understood. This study clarifies the role of surgery and adjuvant therapy when this morphologically distinct tumor is encountered.

METHODS

A systematic search for studies relating to clear cell ependymomas was conducted. Primary outcomes were progression-free survival and overall survival. Prognostic variables were age, sex, tumor consistency, extent of resection, and postoperative adjuvant therapy. Kaplan-Meier survival curves were generated and compared by the log-rank test. Multivariate Cox regression models were constructed, interrogated with Schoenfeld residuals, and used to identify independent prognostic factors.

RESULTS

Of the 384 articles retrieved, 8 articles comprising 77 cases of clear cell ependymoma were included. Five-year overall survival and progression-free survival were 58.1% (95% confidence interval [CI], 46.3%-72.9%) and 46.3% (95% CI, 34.2%-62.8%), respectively. Kaplan-Meier analysis with the log-rank test showed that gross total resection was superior to subtotal resection in prolonging survival (P = 0.047) and delayed time to recurrence (P < 0.01). Multivariate analysis confirmed gross total resection as an independent protective factor against relapse (odds ratio, 0.39; 95% CI, 0.17-0.89; P = 0.03). Age <50 years predicted longer overall survival (odds ratio, 0.16; 95% CI, 0.05-0.49; P < 0.01). Postoperative adjuvant therapy after gross total resection did not affect overall survival (P = 0.98) or progression-free survival (P = 0.93). Adjuvant therapy after subtotal resection favored improved overall survival (P = 0.052).

CONCLUSIONS

Clear cell ependymomas are particularly aggressive in those aged >50 years. Gross total resection remains the cornerstone of management. Postoperative adjuvant therapy is likely to be of survival benefit only after subtotal resection.

Short-term outcome following surgery for rare brain tumor entities in adults: a Swedish nation-wide registry-based study and comparison with SEER database

Objective

To investigate outcomes after surgery for rare brain tumors using the Swedish Brain Tumor Registry (SBTR).

Methods

This is a nationwide study of patient in the SBTR, validated in the Surveillance, Epidemiology, and End Results (SEER) registries. We included all adults diagnosed 2009–2015 with a rare brain tumor entity (n = 216), defined as ependymoma (EP, n = 64), subependymoma (SUBEP, n = 21), ganglioglioma (GGL, n = 54), pilocytic astrocytoma (PA, n = 56) and primitive neuroectodermal tumor (PNET, n = 21). We analyzed symptomatology, tumor characteristics and outcomes.

Results

Mean age was 38.3 ± 17.2 years in GGL, 36.2 ± 16.9 in PA, 37.0 ± 19.1 in PNET, 51.7 ± 16.3 in EP and 49.8 ± 14.3 in SUBEP. The most common symptom was focal deficit (39.6–71.4%), and this symptom was most common in GGL patients with 64.2% of GGL presenting with seizures. Most patients had no or little restriction in activity before surgery (Performance Status 0–1), although up to 15.0% of PNET patients had a performance status of 4. Gross total resection was achieved in most (> 50%) tumor categories. Incidence of new deficits was 11.1–34.4%. In terms of postoperative complications, 0–4.8% had a hematoma of any kind, 1.9–15.6% an infection, 0–7.8% a venous thromboembolism and 3.7–10.9% experienced a complication requiring reoperation. There were 3 deaths within 30-days of surgery, and a 1-year mortality of 0–14.3%.

Conclusion

We have provided benchmarks for the current symptomatology, tumor characteristics and outcomes after surgery for rare brain tumors as collected by the SBTR and validated our results in an independent registry. These results may aid in clinical decision making and advising patients.

Intracranial ependymomas: molecular insights and translation to treatment

Ependymomas are primary central nervous system tumors (CNS), arising within the posterior fossa and supratentorial regions of the brain, and in the spine. Over the last decade, research has resulted in substantial insights into the molecular characteristics of ependymomas, and significant advances have been made in the establishment of a molecular classification system. Ependymomas both within and between the three CNS regions in which they arise, have been shown to contain distinct genetic, epigenetic and cytogenic aberrations, with at least three molecularly distinct subgroups identified within each region. However, these advances in molecular characterization have yet to be translated into clinical practice, with the standard treatment for ependymoma patients largely unchanged. This review summarizes the advances made in the molecular characterization of intracranial ependymomas, outlines the progress made in establishing preclinical models and proposes strategies for moving toward subgroup-specific preclinical investigations and treatment.

Relative survival after diagnosis with a primary brain or other central nervous system tumor in the National Program of Cancer Registries, 2004 to 2014

Background

The majority of reported cancer survival statistics in the United States are generated using the National Cancer Institute's publicly available Surveillance, Epidemiology, and End Results (SEER) data, which prior to 2019 represented 28% of the US population (now 37%). In the case of rare cancers or special subpopulations, data sets based on a larger portion of the US population may contribute new insights into these low-incidence cancers. The purpose of this study is to characterize the histology-specific survival patterns for all primary malignant and nonmalignant primary brain tumors in the United States using the Centers for Disease Control and Prevention's National Program of Cancer Registries (NPCR).

Methods

Survival data were obtained from the NPCR (includes data from 39 state cancer registries, representing 81% of the US population). Relative survival rates (RS) with 95% CI were generated using SEER*Stat 8.3.5 from 2004 to 2014 by behavior, histology, sex, race/ethnicity, and age at diagnosis.

Results

Overall, there were 488 314 cases from 2004 to 2014. Overall 5-year RS was 69.8% (95% CI = 69.6%-69.9%). Five-year RS was 35.9% (95% CI = 35.6%-36.1%) for malignant and 90.2% (95% CI = 90.1%-90.4%) for nonmalignant tumors. Pilocytic astrocytoma had the longest 5-year RS (94.2%, 95% CI = 93.6%-94.6%) of all glioma subtypes, whereas glioblastoma had the shortest 5-year RS (6.1%, 95% CI = 6.0%-6.3%). Nonmalignant nerve sheath tumors had the longest 5-year RS (99.3%, 95% CI = 99.1%-99.4%). Younger age and female sex were associated with increased survival for many histologies.

Conclusions

Survival after diagnosis with primary brain tumor varies by behavior, histology, and age. Using such a database that includes more than 80% of the US population may represent national survival patterns.

Gliomas: survival differences between metropolitan and non-metropolitan counties

BACKGROUND

For gliomas, metropolitan status has not been heavily explored in the context of short-term mortality or long-term observed survival. Larger populations are associated with proximity to academic universities/high-volume hospitals.

METHODS

The SEER-18 registry was queried for patients with gliomas. The patients were further classified into two population groups based on rural-urban continuum codes: metropolitan or non-metropolitan. Demographics and clinical factors were compared between both groups. For observed survival, univariate and multivariate analyses occurred with Cox proportional hazards model.

RESULTS

The non-metropolitan group constituted approximately 10.8% of all patients. Age at diagnosis of glioma was older for the non-metropolitan group compared to metropolitan group (51.60 years vs. 49.06 years). Relative to the metropolitan group, the non-metropolitan group exhibited a larger proportion of Caucasian, married, grade I and IV gliomas, no surgery, no GTR (for those who had surgery), and temporal/parietal/occipital locations. Other covariates (sex, tumor size, laterality, and radiation status) did not exhibit significant differences in proportions. From analysis of observed survival, independent predictors include population group, as well as age, gender, marital status, tumor location, tumor grade, laterality, GTR, and receipt of radiation. Short-term mortality was 11.68% and 13.04% for Metropolitan and non-metropolitan groups, respectively. Median survival was 15 months and 12 months for Metropolitan and non-metropolitan groups, respectively.

CONCLUSIONS

About one-tenth of gliomas are treated at non-metropolitan sites. Key differences exist among patient/glioma characteristics based on metropolitan status. Overall, metropolitan status appears to influence short-term mortality and long-term observed survival for gliomas.

Causes of death in glioblastoma: insights from the SEER database

BACKGROUND

Glioblastoma (GB) and its variants portend a poor prognosis. The predominant cause of death (COD) is related to the cancer diagnosis, but a significant subset is related to other causes. As GB is a systemic disease requiring systemic treatment, focus regarding all COD provides a comprehensive illustration of the disease.

METHODS

The SEER-18 was queried for patients with cranial GB and its variants. Age, gender, race, marital status, tumor characteristics, treatment details, and follow-up data were acquired. The patients were classified into group A (death attributed to this cancer diagnosis) or group B (death attributed to causes other than this cancer diagnosis).

RESULTS

From 1973 to 2013, 36,632 deaths (94%) constituted group A, and 2,324 deaths (5.9%) constituted group B. The latter significantly exhibited lower proportions of age <60, Caucasians, married status, frontal/brain stem/ventricle tumor locations, and receipt of radiation. From logistic regression, age >60, male gender, race, not married, tumor location, and no radiation were significant independent predictors for group B. The top known CODs in group B are diseases of heart, pneumonia and influenza, cerebrovascular diseases, accidents and adverse effects, and infections.

CONCLUSIONS

CODs not attributed to GB remains a significant subset of all CODs. Many of these, particularly diseases of heart, are frequent comorbidities. Moreover, infection-related CODs after GB diagnosis appear more salient compared to CODs in the general population. Consideration of these CODs, and vigilant treatment aimed at these CODs, may improve overall care for GB patients.

Diagnostics of pediatric supratentorial RELA ependymomas: integration of information from histopathology, genetics, DNA methylation and imaging

Ependymoma with RELA fusion has been defined as a novel entity of the revised World Health Organization 2016 classification of tumors of the central nervous system (CNS), characterized by fusion transcripts of the RELA gene and consequent pathological activation of the NFkB pathway. These tumors represent the majority of supratentorial ependymomas in children. The validation of diagnostic tools to identify this clinically relevant ependymoma entity is essential. Here, we have used interphase fluorescent in situ hybridization (FISH) for C11orf95 and RELA, immunohistochemistry (IHC) for p65‐RelA and the recently developed DNA methylation‐based classification besides conventional histopathology, and compared the precision of the methods in 40 supratentorial pediatric brain tumors diagnosed as ependymomas in the past years. Reverse transcription PCR (RT‐PCR) and RNA sequencing were performed to explore discordant cases. Furthermore, we integrated imaging and clinical features as additional layers of information. The concordance between nuclear RelA expression by IHC and RELA FISH was 100%. Concordance between IHC and DNA methylation profiling, and between FISH and DNA methylation profiling was also high (96.4% and 95.2%, respectively). Thirty‐four out of 40 (85%) cases were confirmed by integrated diagnoses as ependymal tumors, including 22 RELA‐fused ependymomas (71% of ependymal tumors), two YAP1‐fused ependymomas (6%), six non‐RELA/non‐YAP1 ependymomas (18%) and four ependymal/subependymal mixed tumors (12%). Ependymal/subependymal mixed tumors had an excellent clinical outcome despite the presence of histopathological signs of malignancy, suggesting that these tumors should not be diagnosed as classic ependymomas. DNA methylation profiling helped in the differential diagnosis of RELA‐fused ependymomas. IHC and FISH, which are available in the majority of pathology laboratories, are valuable tools to identify RELA‐fused ependymomas.

Glioblastoma in the setting of prior lower grade gliomas - insights from SEER database

Introduction

Secondary glioblastomas (GBs) constitute a small subset of all GBs and tend to arise after a lower grade glioma. Though knowledge regarding this subset has gained traction in recent years, its definition continues to evolve, complicating its clinical management. Investigation of epidemiology and survival patterns may help provide needed insights.

Results

The age at GB diagnosis is significantly lower (46.22 vs 60.25 years) for group B. The distribution among type of GB (glioblastoma, giant cell glioblastoma, or gliosarcoma) was significantly different, with no diagnosis of giant cell GB in Group B. Compared to Group A, Group B exhibited a higher proportion of females, not married, smaller tumors, no GTR, and no radiation (all p < 0.05). GB-related observed survivals were comparable. Cox regression with inclusion of co-variates reveal no significant influence of GB group on observed survival. Regarding group B, mean age was 40.197 for diagnosis of initial lower grade glioma. The most common initial ICD-O-3 pathology was oligodendroglioma, NOS; astrocytoma, NOS; astrocytoma, anaplastic; and mixed glioma.

Methods

The SEER-18 registry was queried for patients with GBs. Patients were further classified into two GB groups: Group A – those with GB as the only primary tumor, and Group B – those with GB as a 2^nd primary or subsequent tumor and with history of lower grade gliomas. Demographics and clinical factors were compared between group A and B. Appropriate statistics were employed to calculate incidences and differences among factors and GB-related survivals between the groups.

Conclusions

Overall, Group B develops GBs at an earlier age, but observed survival remains similar to those with GBs as the only primary. Moreover, this subset also exhibit different proportions of the types of GBs, and well as differences in other key clinical factors (namely, gender and tumor size at presentation). Prior treatments for lower grade gliomas likely explain some of the differences noted regarding management course after diagnosis of GB.

Surgical management and long-term outcome of intracranial subependymoma

BACKGROUND

Intracranial subependymomas account for 0.2-0.7% of central nervous system tumours and are classified as World Health Organization (WHO) grade 1 tumours. They are typically located within the ventricular system and are detected incidentally or with symptoms of hydrocephalus. Due to paucity of studies exploring this tumour type, the objective was to determine the medium- to long-term outcome of intracranial subependymoma treated by surgical resection.

METHODS

Retrospective case note review of adults with intracranial WHO grade 1 subependymoma diagnosed between 1990 and 2015 at the Walton Centre NHS Foundation Trust was undertaken. Tumour location, extent of resection (defined as gross total resection (GTR), sub-total resection (STR) or biopsy) and the WHO performance status at presentation and through follow-up were recorded.

RESULTS

Thirteen patients (7 males; 6 females) with a mean age of 47.6 years (range 33-58 years) and a median follow-up of 46 months (range 25-220 months) were studied. Eight patients had symptomatic tumours (headache, visual disturbance); five had incidental finding. Tumours were most commonly located in the fourth ventricle (n = 8). The performance status scores at diagnosis were 0 (n = 8) and 1 (n = 5). The early post-operative performance status scores at 6 months were 0 (n = 5) and 1 (n = 8) and at last follow-up were 0 (n = 11) and 1 (n = 2). There was no evidence of tumour re-growth following GTR or STR. The commonest complication was hydrocephalus (n = 3).

CONCLUSION

Subependymoma are indolent tumours. No patients exhibited a worsening of performance status at medium- to long-term follow-up and there were no tumour recurrence suggesting a shorter follow-up time may be sufficient. Surgical resection is indicated for symptomatic tumours or those without a clear imaging diagnosis. Incidental intraventricular subependymoma can be managed conservatively through MRI surveillance.

Intracranial hemangioblastoma - A SEER-based analysis 2004-2013

Introduction

Intracranial hemangioblastoma (HB) is a rare pathology. Limited data exist regarding its epidemiology.

Methods

With the SEER-18 registry database, information from all patients diagnosed with intracranial HB from 2004 to 2013 were extracted, including age, gender, race, marital status, presence of surgery, extent of surgery, receipt of radiation, tumor size, tumor location, and follow-up data. Age-adjusted incidence rates and overall survival (OS). Cox proportional hazards model was employed for both univariate and multivariate analyses.

Results

A total of 1307 cases were identified. The overall incidence of intracranial hemangioblastoma is 0.153 per 100,000 person-years [95% confidence interval (CI)=0.145–0.162]. Through univariate analysis, age < 40 [hazard ratio (HR)=0.277, p<0.001], no radiation [HR=0.56, p=0.047], and presence of surgery [HR=0.576, p=0.012] are significant positive prognostic factors. Caucasian race [HR=1.42, p=0.071] and female gender [HR=0.744, p=0.087] exhibit noticeable trends towards positive prognosis. Through multivariate analysis, younger age [HR=1.053, p < 0.01], race [HR=1.916, p<0.01], and presence of surgery [HR=0.463, p<0.01 were significant independent prognostic factors.

Conclusion

Clinical factors such as younger age, Caucasian race, and presence of surgery are significant independent factors for overall survival in patients with HBs. Though analysis regarding extent of surgery did not produce a meaningful relationship, this may be related to surgical bias / expertise. Moreover, no validation for radiation therapy was identified, but this may be related to short follow up intervals and the variable growth patterns of HBs.