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Central nervous system Childhood

Ependymoma

Ependymoma is a glial tumour that usually grows from the lining of the ventricles or the central canal of the spinal cord. This entry covers posterior-fossa tumours in children and surgery.

17 min read Updated September 24, 2026 3,669 words

Medically reviewed Last reviewed September 24, 2026

1. Introduction and Overview

Ependymoma is a primary central nervous system (CNS) tumor arising from the ependymal cells lining the ventricular system of the brain and the central canal of the spinal cord. As a glial neoplasm, it belongs to the broader family of gliomas but possesses distinct clinical, histological, and molecular characteristics that dictate a unique management paradigm.

While relatively rare—accounting for approximately 1.9% of all primary brain and CNS tumors—ependymomas are the third most common pediatric brain tumor (following pilocytic astrocytoma and medulloblastoma) and represent a significant cause of neurological morbidity in both children and adults. The disease exhibits a bimodal age distribution: a peak in young children (intracranial, often posterior fossa) and a second peak in adults (spinal cord).

Key Defining Features:

  • Origin: Ependymal cells (neuroepithelial lineage).
  • WHO Classification (CNS WHO 2021): Defined by anatomical location (supratentorial, posterior fossa, spinal) and molecular drivers (e.g., ZFTA fusion, YAP1 fusion, MYCN amplification, H3 K27M alteration).
  • Grading: WHO Grade 2 (low-grade) or WHO Grade 3 (anaplastic/high-grade). Note: The term “ependymoblastoma” is obsolete; “subependymoma” and “myxopapillary ependymoma” are now classified as distinct, Grade 1 entities.
  • Spread: Primarily local infiltration and CSF dissemination (drop metastases); hematogenous spread is exceedingly rare.

2. Epidemiology and Risk Factors

Understanding who is affected helps frame clinical suspicion and screening protocols.

Incidence and Demographics

Parameter Statistical Overview
Annual Incidence (US) ~1,300–1,500 new cases/year (CBTRUS data).
Age Distribution Bimodal: Peak 1: 0–4 years (intracranial); Peak 2: 30–50 years (spinal).
Sex Predilection Slight male predominance (M:F ≈ 1.1:1 to 1.3:1) overall; varies by subgroup.
Location by Age Pediatric: ~90% intracranial (60-70% posterior fossa).<br>Adult: ~60% spinal, 40% intracranial.
Race/Ethnicity Slightly higher incidence in White populations compared to Black or Asian populations.

Etiology and Risk Factors

The vast majority of ependymomas are sporadic, with no identifiable environmental cause.

  • Ionizing Radiation: The only established environmental risk factor. Cranial irradiation for prior malignancies (e.g., ALL, retinoblastoma) increases the risk of secondary ependymomas, typically with a latency period of 10–20 years.
  • Genetic Syndromes: Neurofibromatosis Type 2 (NF2) is strongly associated with spinal ependymomas (especially intramedullary) and myxopapillary ependymomas. Germline NF2 mutations are found in ~50% of spinal ependymoma patients with NF2.
  • Developmental Factors: The peak in infancy suggests a potential link to aberrant neurodevelopmental pathways, though specific teratogens remain unidentified.

3. Molecular Classification: The Modern Diagnostic Framework

The WHO CNS 5th Edition (2021) revolutionized ependymoma classification by integrating molecular profiling with histology and location. This stratification is now mandatory for diagnosis, prognostication, and clinical trial enrollment.

The Four Major Molecular Groups

Molecular Group Anatomical Location Key Molecular Driver Typical Age WHO Grade Prognosis
PF-EPN-A (Posterior Fossa Group A) Posterior Fossa H3 K27M-altered (loss of H3K27me3) / Polycomb repression Infants / Young Children (< 5 yrs) 2 or 3 Poor (High recurrence, resistant to chemo)
PF-EPN-B (Posterior Fossa Group B) Posterior Fossa Retained H3K27me3; Hypermethylation distinct from A Older Children / Adults 2 or 3 Favorable (Better PFS/OS)
ST-EPN-ZFTA (Supratentorial ZFTA-fusion) Supratentorial (Hemispheres) ZFTA::RELA* fusion (C11orf95-RELA) Children / Young Adults 3 (Anaplastic) Intermediate/Poor
ST-EPN-YAP1 (Supratentorial YAP1-fusion) Supratentorial (Hemispheres) YAP1::MAMLD1* fusion Infants / Young Children 2 or 3 Favorable
SP-EPN (Spinal) Spinal Cord / Filum Terminale NF2 mutations (sporadic & NF2-related); MYCN amp (rare, aggressive) Adults (30-50 yrs) 2 (mostly) Excellent (if GTR achieved)

Clinical Pearl:** Myxopapillary Ependymoma (WHO Grade 1) and Subependymoma (WHO Grade 1) are now distinct diagnostic entities separated from the diffuse ependymoma groups above. They carry excellent prognoses but require distinct surgical strategies.

4. Histopathology: How Does It Look?

This section details the macroscopic (surgical/radiological) and microscopic (histological) appearance critical for diagnosis.

Macroscopic and Radiological Appearance (“How It Looks on Imaging”)

Ependymomas are typically well-circumscribed but not encapsulated masses arising from the ventricular lining or central canal.

A. Posterior Fossa (Fourth Ventricle) – “The Classic Plastic Tumor”

  • MRI T1: Iso- to hypointense relative to gray matter.
  • MRI T2/FLAIR: Heterogeneously hyperintense.
  • Contrast Enhancement: Vivid, heterogeneous enhancement in >90% of cases.
  • Key Morphology: Tumor extends out the foramina of Luschka (CP angle) and Magendie (prepontine cistern), wrapping around the brainstem and cerebellar peduncles. This “plastic” growth insinuating into CSF spaces is a hallmark radiographic sign.
  • Calcifications: Present in ~50% (blooming on SWI/GRE sequences).
  • Cysts: Intratumoral cysts common; peritumoral edema is usually mild or absent unless the tumor is high-grade (Grade 3) or causes obstructive hydrocephalus.
  • Hydrocephalus: Near-universal at presentation due to fourth ventricle obstruction.

B. Supratentorial (Lateral/Third Ventricle)

  • Location: Often centered in the lateral ventricles (trigone/body) or third ventricle.
  • Appearance: Large, heterogeneous mass with solid and cystic components.
  • Hemorrhage: High frequency of intratumoral hemorrhage (T1 hyperintensity, SWI blooming) – more common than in posterior fossa tumors.
  • Calcifications: Frequent, often coarse.
  • Edema: Moderate to significant peritumoral vasogenic edema (T2/FLAIR hyperintensity extending into white matter), often disproportionate to size compared to PF tumors.

C. Spinal Ependymoma

  • Intramedullary (Cord): Well-circumscribed, eccentric mass expanding the cord.
  • “Cap Sign” (Hemosiderin Cap): T2 hypointensity at superior/inferior poles due to chronic microhemorrhage (seen in ~20-30%, highly specific).
  • Syringomyelia: Associated syrinx (non-enhancing cystic cavity) rostral/caudal to tumor in ~50%.
  • Enhancement: Intense, homogeneous.
  • Myxopapillary Ependymoma (Filum Terminale/Conus): Sausage-shaped, encapsulated mass in the cauda equina. Intense enhancement. May show “sugar-coating” of nerve roots.

D. Subependymoma (Incidental Finding)

  • Usually asymptomatic, intraventricular nodule (lateral ventricle > fourth ventricle).
  • Non-enhancing or minimal patchy enhancement.
  • Low T2 signal relative to diffuse ependymoma (dense cellularity/fibrosis).

Microscopic Appearance (Histopathology)

Diagnosis requires neuropathology review of formalin-fixed paraffin-embedded (FFPE) tissue.

Feature WHO Grade 2 (Diffuse Ependymoma) WHO Grade 3 (Anaplastic Ependymoma)
Cellularity Moderate Markedly increased
Mitotic Activity Rare / Absent (< 4 per 10 HPF) Frequent / Brisk (≥ 4 per 10 HPF)
Nuclear Atypia Mild to moderate (uniform oval nuclei) Marked pleomorphism, hyperchromasia, irregular membranes
Microvascular Proliferation (MVP) Absent Present (endothelial hyperplasia, glomeruloid bodies)
Necrosis Absent Present (pseudopalisading or geographic)
Ependymal Rosettes Classic: Tumor cells arranged around a central lumen (resembling ventricular lining). Often disrupted/disorganized; may be scarce.
Perivascular Pseudorosettes Hallmark: Tumor cells radially arranged around blood vessels (ependymal processes toward vessel). Present but architecture chaotic.
Special Stains GFAP: Positive (cytoplasmic processes).<br>EMA (Epithelial Membrane Antigen): Dot-like positivity in perinuclear region (highly specific).<br>S100: Variable.<br>Ki-67 (MIB-1): Low (< 5-10%). Ki-67: Elevated (> 10-15%, often >20%).<br>H3K27me3: Loss of nuclear staining confirms PF-EPN-A.

Diagnostic Pitfall: Distinguishing Grade 2 from Grade 3 relies strictly on the presence of mitotic activity AND microvascular proliferation (MVP)**. Necrosis alone without MVP is insufficient for Grade 3 designation in current criteria. Molecular grouping (e.g., PF-EPN-A) often overrides histologic grade for prognosis.

5. Clinical Presentation: Symptoms

Symptomatology is dictated almost entirely by tumor location, size, growth rate, and patient age. Symptoms evolve over weeks to months (indolent) or days (acute hydrocephalus/hemorrhage).

Posterior Fossa Ependymoma (Pediatric Predominance)

A. Symptoms of Obstructive Hydrocephalus (Most Common Initial Presentation)

  • Headache: Classically worse in the morning or upon waking (due to nocturnal CO2 retention/vasodilation), improves with upright posture. Vomiting often projectile, non-bilious, relieves headache transiently.
  • Papilledema: Fundoscopic finding of blurred disc margins, venous engorgement, loss of spontaneous venous pulsations. Critical sign in cooperative children.
  • Cranial Nerve VI Palsy (Abducens): False localizing sign from increased ICP → horizontal diplopia (esotropia).
  • Irritability / Lethargy / Developmental Regression: In infants/toddlers (inability to verbalize headache).
  • Macrocephaly / Bulging Fontanelle / Sutural Diastasis: In infants with open sutures (< 18 months).

B. Cerebellar / Brainstem Signs (Local Invasion)

  • Truncal Ataxia: Wide-based gait, titubation (trunkal tremor), inability to sit/stand unsupported. Distinct from appendicular ataxia.
  • Cranial Nerve Deficits:
  • CN VII/VIII (CPA extension): Facial weakness, hearing loss, tinnitus, vertigo.
  • CN IX/X (Foramen of Magendie): Dysphagia, hoarseness, aspiration risk, gag reflex loss.
  • CN XII: Tongue deviation/atrophy.
  • Nystagmus: Gaze-evoked or downbeat (tonsillar herniation/compression).

C. Acute Catastrophic Presentations

  • Tonsillar Herniation: Sudden apnea, bradycardia, hypertension (Cushing’s triad), coma – requires emergent ventriculostomy/resection.
  • Intratumoral Hemorrhage: Sudden severe headache, rapid neurological decline (more common in supratentorial but occurs in PF).

Supratentorial Ependymoma

  • Seizures: Most common presenting symptom in adults/adolescents (50-70%). Focal onset (motor, sensory, temporal lobe automatisms) potentially generalizing. Often refractory to medication.
  • Focal Neurological Deficits: Hemiparesis, hemisensory loss, visual field cuts (homonymous hemianopia), aphasia (dominant hemisphere).
  • Headache / Nausea / Vomiting: Signs of elevated ICP (mass effect + hydrocephalus if third ventricle/foramen of Monro involved).
  • Cognitive/Personality Changes: Frontal lobe tumors → apathy, disinhibition, executive dysfunction.
  • Endocrine Dysfunction: Third ventricle tumors → hypothalamic/pituitary axis disruption (DI, growth failure, precocious puberty).

Spinal Ependymoma (Adult Predominance)

A. Intramedullary (Cervical > Thoracic > Lumbar)

  • Pain: #1 Symptom. Local back/neck pain (deep, aching, worse at night/lying flat). Radicular pain (shooting, dermatomal) due to root compression.
  • Sensory Deficits: “Cape-like” sensory loss (suspended sensory loss) – loss of pain/temperature over shoulders/upper arms (spinothalamic tract decussation anteriorly) with preserved light touch (dorsal columns posterior). Posterior column loss → proprioception/vibration loss in feet.
  • Motor Deficits: Spastic weakness (UMN signs: hyperreflexia, clonus, Babinski) below lesion level. Asymmetric onset common.
  • Bowel/Bladder Dysfunction: Urinary urgency, hesitancy, retention, incontinence (late sign = conus/cauda equina involvement).
  • Scoliosis/Torticollis: In children, asymmetric paraspinal spasm may be the first sign.

B. Myxopapillary Ependymoma / Filum Terminale (Conus/Cauda Equina)

  • Radicular Pain: Severe, often bilateral sciatica/leg pain.
  • Saddle Anesthesia: Perineal/perianal numbness.
  • Bowel/Bladder/Sexual Dysfunction: Early and prominent (lower motor neuron: flaccid paralysis, areflexia).
  • Lower Extremity Weakness: Flaccid, areflexic (LMN) if cauda equina; spastic if conus involved.

Symptom Summary by Age Group

Age Group Most Common Presenting Symptoms “Red Flag” Requiring Urgent Imaging
Infants (0-2 yrs) Macrocephaly, vomiting, irritability, sunset gaze, developmental delay/loss of milestones. Bulging fontanelle, split sutures, Cushing’s triad.
Children (3-12 yrs) Morning headache + vomiting, ataxia/gait disturbance, cranial nerve palsies, school performance decline. Acute onset diplopia, rapid gait deterioration, papilledema.
Adolescents/Young Adults Headache, seizures (supratentorial), focal weakness, back pain/radiculopathy (spinal). New-onset seizure, progressive focal deficit.
Adults (>25 yrs) Spinal: Back pain, radiculopathy, sensory/motor level, sphincter disturbance.<br>Brain: Seizure, headache, focal deficit. Progressive myelopathy, cauda equina syndrome (saddle anesthesia + retention).

6. Diagnostic Workup

A stepwise approach ensures accurate diagnosis, staging, and molecular classification.

Neuroimaging (Gold Standard)

  1. MRI Brain & Spine with/without Gadolinium: Mandatory baseline.
  • Brain: High-resolution T1, T2, FLAIR, DWI/ADC, SWI/GRE (hemorrhage/calcification), Post-contrast T1 (thin slice, 3D).
  • Spine: Entire neuraxis (cervical, thoracic, lumbar) with fat suppression post-contrast to detect drop metastases (leptomeningeal dissemination). Performed pre-operatively or within 24-48 hrs post-op (to distinguish surgical artifact from true dissemination).
  1. CT Head: Rapid assessment for hydrocephalus, calcification, hemorrhage in emergency settings.

Histopathology & Molecular Diagnostics (Tissue Required)

  • Maximal Safe Resection provides tissue for diagnosis.
  • Immunohistochemistry (IHC) Panel: GFAP, EMA (dot-like), Ki-67, H3K27me3 (loss = PF-EPN-A), INI1/SMARCB1 (retained), OLIG2.
  • Methylation Profiling (Array-based): Current Gold Standard for molecular grouping (PF-A, PF-B, ST-ZFTA, ST-YAP1, SP). Performed on FFPE or fresh frozen tissue.
  • FISH / RT-PCR / NGS Panel: Targeted detection of ZFTA::RELA, YAP1 fusions, NF2 mutations, MYCN amplification if methylation unavailable.
  • Germline Testing: Recommended for all spinal ependymomas (NF2 testing) and pediatric patients with specific features.

Staging Investigations (Post-Op / Pre-RT)

  • Post-operative MRI (Brain): Within 24–48 hours to assess Extent of Resection (EOR) – the single strongest modifiable prognostic factor.
  • Post-operative MRI Spine: If not done pre-op, wait 2–3 weeks post-op to avoid false positives from surgical blood products.
  • CSF Cytology: Lumbar puncture > 14 days post-op (avoids false positives from surgical cell shedding). Minimum 10 mL CSF; cytospin preparation.
  • Baseline Neurocognitive / Endocrine / Audiology / Visual Field Testing: Prior to radiotherapy.

7. Treatment Strategies: A Multimodal Approach

Management requires a Multidisciplinary Tumor Board (MDT) including Neurosurgery, Neuro-Oncology, Radiation Oncology, Neuropathology, Neuroradiology, and supportive care.

Surgery: The Cornerstone of Cure

Goal: Gross Total Resection (GTR) – complete macroscopic removal.

  • Prognostic Impact: GTR improves 5-year PFS from ~30-50% (STR) to 65-85% (depending on molecular group).
  • Nuance: “Maximal Safe Resection.” Sacrificing neurological function (brainstem/cranial nerves, motor tracts) for GTR is contraindicated if high morbidity is predicted. Intraoperative neurophysiological monitoring (IONM: MEP, SSEP, BAEP, CN monitoring) is standard of care.
  • Second-Look Surgery: Strongly considered if initial resection is Subtotal (STR) and residual is accessible. Converts STR → GTR, improving outcome.
  • CSF Diversion: EVD/VP Shunt for hydrocephalus. Endoscopic Third Ventriculostomy (ETV) preferred in older children/adults to avoid shunt dependence; often performed at time of resection.

Radiotherapy (RT): The Critical Adjuvant

  • Indication:
  • WHO Grade 3 (All locations): Mandatory post-op (GTR or STR).
  • WHO Grade 2:
  • Posterior Fossa: Standard after STR. Controversial after GTR (PF-EPN-B may be observed; PF-EPN-A usually treated).
  • Supratentorial: Standard after STR; often recommended after GTR for ST-EPN-ZFTA.
  • Spinal: After STR; rarely needed after GTR for Grade 2 (except MYCN amp).
  • Technique: Conformal 3D-CRT or IMRT/VMAT. Proton Beam Therapy (PBT) strongly preferred for pediatric patients (< 18-25 yrs) and tumors near critical structures (brainstem, cochlea, hypothalamus, spinal cord) to reduce integral dose and late toxicity (neurocognitive, endocrine, auditory, secondary malignancy).
  • Dose/Fractionation:
  • Tumor Bed: 54–59.4 Gy (Grade 3 / Residual disease).
  • Tumor Bed: 50.4–54 Gy (Grade 2 GTR, if indicated).
  • Note: Whole CNS irradiation (craniospinal irradiation – CSI) NOT standard for localized disease. Reserved for M+ disease (metastatic).
  • Target Volume: Involved Field (IFRT) or Tumor Bed + Margin. Elective nodal irradiation not required.

Systemic Therapy (Chemotherapy / Targeted Therapy)

  • Standard Chemotherapy: Limited efficacy in newly diagnosed disease. No regimen has proven survival benefit over RT alone in randomized trials for standard risk.
  • Role: Deferral of RT in very young children (< 3 yrs) using multi-agent regimens (e.g., Vincristine, Cyclophosphamide, Cisplatin, Etoposide – “Baby POG” / SIOP protocols / ACNS0121 backbone) until RT is safer (age 3+).
  • Maintenance: Not standard.
  • Recurrent Disease: Salvage chemotherapy (Oral Etoposide, Temozolomide, Bevacizumab +/- Irinotecan, Platinum-based) + Re-irradiation (SRS/FSRT) + Re-operation.
  • Targeted Therapy / Clinical Trials (Active Areas):
  • PF-EPN-A: EZH2 inhibitors (Tazemetostat), HDAC inhibitors, BET inhibitors (targeting epigenetic dysregulation).
  • ST-EPN-ZFTA: NF-κB pathway inhibitors, HDAC inhibitors.
  • Immunotherapy: Checkpoint inhibitors (low TMB, generally cold tumors), CAR-T (IL13Rα2, EGFRvIII, B7-H3 targets under investigation).
  • DNA Damage Response: PARP inhibitors (preclinical rationale).

8. Prognosis and Survival Outcomes

Prognosis is multivariate: Molecular Group > Extent of Resection (EOR) > Histologic Grade > Age > Metastatic Status.

Survival Statistics (Approximate 5-Year PFS / OS)

Group / Scenario 5-Year PFS 5-Year OS Key Modifiers
PF-EPN-A (Child) 30–45% 50–65% GTR + RT improves PFS to ~50-60%. High relapse rate.
PF-EPN-B (Child/Adult) 70–85% 85–95% Excellent with GTR ± RT.
ST-EPN-ZFTA 50–65% 65–75% Aggressive; GTR + RT mandatory.
ST-EPN-YAP1 80–90% >90% Favorable; GTR often curative.
Spinal (Grade 2, GTR) 85–95% >95% Surgery alone often curative.
Spinal (Grade 3 / MYCN amp) 40–60% 50–70% Requires RT; high recurrence risk.
M+ Disease (Disseminated) 30–50% 40–60% CSI + Chemo + Local boost.

Critical Concept: Recurrence is usually LOCAL** (at primary site) in >80% of cases. Distant CSF dissemination at recurrence is less common but portends very poor survival.

Late Effects and Survivorship (Critical for Quality of Life)

Long-term survivors face significant morbidity requiring lifelong surveillance.

Domain Specific Risks Surveillance / Intervention
Neurocognitive IQ decline, processing speed, working memory, executive function (RT dose/volume to supratentorial brain/temporal lobes). Annual neuropsych testing; school IEP/504 plans; cognitive rehab.
Endocrine Growth Hormone Deficiency (GHD), Hypothyroidism, Puberty disorders, Obesity/MetS, Adrenal insufficiency (Hypothalamic/Pituitary RT > 30-40 Gy). 6-12 monthly endocrine panel; GH replacement; thyroid replacement.
Audiovestibular Sensorineural hearing loss (Cisplatin chemo + RT to cochlea/posterior fossa). Annual audiograms; hearing aids/cochlear implant.
Secondary Malignancies Meningioma, Glioma, Sarcoma (RT field), Thyroid CA (spine RT scatter). Annual clinical exam; MRI surveillance; thyroid US if neck irradiated.
Vasculopathy Moyamoya syndrome, Stroke (RT vasculopathy). MRA surveillance; aspirin prophylaxis controversial.
Musculoskeletal Kyphoscoliosis (Spinal RT in young children), Growth asymmetry. Ortho referral; bracing/surgery.
Fertility Gonadal damage (Cyclophosphamide/Procarbazine/Cisplatin + Pelvic/Spinal RT). Sperm/Oocyte banking pre-treatment; fertility counseling.

9. Follow-Up Protocol (Surveillance Imaging)

Standard schedule for localized disease post-RT completion (adjust per protocol/MDT):

Time Post-RT Brain MRI Spine MRI Clinical / Labs
0–3 months Baseline (1 mo post-RT) Baseline (if not recent) Neuro exam, Endocrine, Neurocog baseline
Year 1 Every 3 months Every 6 months q3-6 mo clinic
Year 2 Every 4 months Every 6 months q6 mo clinic
Year 3 Every 6 months Every 12 months q6-12 mo clinic
Year 4-5 Every 6-12 months Every 12-24 months Annual clinic
Year 5+ Annual (or q2y if stable) As indicated / q2-3y Annual survivorship clinic

Note: Any new neurological symptom warrants immediate imaging regardless of schedule. “Pseudoprogression” (transient enhancement/edema 1-6 mo post-RT) mimics recurrence; requires clinical correlation, advanced imaging (perfusion, spectroscopy, PET), or biopsy.

10. Special Populations & Clinical Scenarios

Pediatric Patients < 3 Years (The “Young Child” Dilemma)

  • Challenge: Avoid/defer Craniospinal Irradiation (CSI) and high-dose focal RT to prevent catastrophic neurocognitive/endocrine sequelae.
  • Strategy: Maximal Safe Resection → Intensive Chemotherapy (High-dose + Autologous Stem Cell Rescue often used) → Deferred Focal RT at Age 3-5 years.
  • Outcome: Inferior to upfront RT for PF-EPN-A; reasonable for PF-EPN-B / ST-EPN-YAP1. Molecular grouping guides intensity.

NF2-Associated Spinal Ependymomas

  • Multiplicity: Multiple synchronous tumors (cervical, thoracic, lumbar) + vestibular schwannomas + meningiomas.
  • Management: Symptom-directed surgery only. Do not operate on asymptomatic lesions. RT reserved for progressive symptomatic tumors not amenable to surgery (radiosurgery/SRS preferred to preserve cord tolerance). Bevacizumab shows activity for vestibular schwannomas; role in ependymoma unclear.

Pregnancy

  • Diagnosis: MRI without Gadolinium (Gd contraindicated).
  • Surgery: Safe in 2nd trimester (14-28 wks) if symptomatic/progressive. Delay if asymptomatic/indolent until postpartum.
  • RT: Contraindicated. Chemo: Highly teratogenic 1st trimester; limited options 2nd/3rd.
  • Delivery: Vaginal delivery usually possible; C-section for obstetric indications only.

11. Patient and Caregiver Education: Living with Ependymoma

Questions to Ask Your Care Team

  1. What is the exact molecular subgroup? (PF-A, PF-B, ST-ZFTA, ST-YAP1, Spinal). This drives everything.
  2. Was Gross Total Resection achieved? (Check post-op MRI report).
  3. Is Radiotherapy recommended? Why/Why not? (Protons vs Photons?).
  4. Am I / Is my child eligible for a Clinical Trial? (Especially for PF-EPN-A or Recurrent disease).
  5. What is the plan for Fertility Preservation? (Before chemo/RT).
  6. What late effects should we monitor for specifically?
  7. Who coordinates Survivorship Care long-term?

Red Flags Requiring Immediate Medical Attention

  • Acute: Sudden severe headache, vomiting, lethargy, weakness, seizure, difficulty breathing (herniation/hydrocephalus/hemorrhage).
  • Subacute: New/worsening gait imbalance, facial asymmetry, swallowing difficulty, double vision.
  • Spinal: New bowel/bladder incontinence, saddle numbness, rapidly progressing weakness (cord compression/syrinx).

Support Resources

  • CERN Foundation / Ependymoma Outcomes Projects: Patient registries, education, research funding.
  • ABTA (American Brain Tumor Association), NBTS (National Brain Tumor Society), CBTN (Children’s Brain Tumor Network).
  • Local Neuro-Oncology Social Work / Palliative Care Teams: Early integration improves quality of life, not just end-of-life.

12. Future Directions and Research Horizons

  1. Molecularly Stratified Trials: Moving away from “one size fits all” RT/Chemo. Trials like ACNS1831 (testing chemo + RT for PF-EPN-A) and SJEPN21 (molecular risk-adapted therapy).
  2. Liquid Biopsy (ctDNA/ctRNA in CSF): Detecting minimal residual disease (MRD) and monitoring recurrence months before MRI changes. H3K27M mutant allele fraction in CSF correlates with tumor burden.
  3. Epigenetic Reprogramming: Targeting the Polycomb Repressive Complex 2 (PRC2) dysfunction in PF-EPN-A (EZH2 inhibitors, menin inhibitors).
  4. Blood-Brain Barrier Disruption: Focused Ultrasound (FUS) + BBB opening for enhanced drug delivery.
  5. Immunotherapy Optimization: Overcoming the “cold” tumor microenvironment (low mutational burden, low TILs) via combination strategies (RT + STING agonists, vaccines).

13. Glossary of Key Terms

  • Anaplastic: Histologically high-grade (WHO Grade 3), showing high mitotic activity, microvascular proliferation, and/or necrosis.
  • Craniospinal Irradiation (CSI): Radiation delivered to the entire brain and spinal cord.
  • Drop Metastases: Tumor cells seeding the spinal subarachnoid space via CSF flow (caudal dissemination).
  • Extent of Resection (EOR): GTR (Gross Total Resection), NTR (Near Total Resection <1.5 cm² resid.), STR (Subtotal Resection), Biopsy.
  • H3K27me3: Histone 3 Lysine 27 trimethylation. Loss of immunohistochemical staining is a surrogate marker for the aggressive PF-EPN-A subgroup.
  • Hydrocephalus: Accumulation of CSF causing ventricular dilation and increased intracranial pressure.
  • Leptomeningeal Dissemination: Spread of tumor cells along the meninges (pia/arachnoid) via CSF.
  • Maximal Safe Resection: Removing as much tumor as possible without causing new permanent neurological deficit.
  • Molecular Subgroup: Classification based on DNA methylation, gene fusions, or mutations (e.g., PF-EPN-A, ST-EPN-ZFTA).
  • Myxopapillary Ependymoma (MPE): WHO Grade 1 tumor of the filum terminale/cauda equina, distinct from diffuse ependymoma.
  • Pseudoprogression: Treatment-related imaging changes (enhancement/edema) mimicking tumor progression, typically 1-6 months post-RT.
  • Syringomyelia / Syrinx: Fluid-filled cavity within the spinal cord parenchyma, often associated with spinal tumors.
  • ZFTA::RELA Fusion: Pathognomonic gene fusion (C11orf95-RELA) defining ST-EPN-ZFTA, activating NF-κB pathway.

References

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  2. Wefel, J.S. et al. (2022) ‘Ependymoma’, in DeVita, Hellman, and Rosenberg’s Cancer: Principles & Practice of Oncology. 12th edn. Philadelphia: Lippincott Williams & Wilkins, pp. 1845–1868.
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