Ependymal Tumors - KS

Question 1

Ependymomas are currently classified based on _________ and ___________________. They are WHO grade 2 or 3.

Answer 1

location and molecular changes

Question 2

What are the three locations for ependymoma classification?

Answer 2

-Supratentorial
-Posterior Fossa
-Spinal Cord

Question 3

Supratentorial Ependymoma molecular subgroups (2)

Answer 3

-YAP1-fusion
-ZFTA-fusion (c11orf95) - fused with RELA

Question 4

Posterior Fossa Ependymoma molecular subgroups (2)

Answer 4

• Group A: Loss of H3 p.K28me3 (H27me3)
• Group B: Retained H3 p.K28me3 (H27me3) expression

Question 5

Spinal Cord Ependymoma subgroups

Answer 5

-MYCN amplified
-NOT MYCN amplified (frequent loss of chromosome 22q

Question 6

Supratentorial Ependymoma, YAP1 fusion-positive:
-Fusion partner gene

Answer 6

MAMLD1

*YAP1::MAMLD1 fusions function as an oncogenic driver through the recruitment of nuclear factor 1 (FN1) and TEA domain (TEAD) family members

Question 7

Supratentorial Ependymoma, YAP1 fusion-positive:
-Location
-Age/Sex
-Prognosis

Answer 7

-Lateral Ventricle (within or adjacent to)
-Young children/Female predominant (M:F=0.3:1.0)
-Favorable prognosis

Question 8

Supratentorial Ependymoma, ZFTA fusion-positive (formerly C11orf95):
-Fusion partner gene
-IHC (3)

Answer 8

-RELA
-ZFTA::RELA fusion show nuclear accumulation of p65 protein and universal cytoplasmic expression of L1CAM; also cyclinD1 (KS)

Question 9

Supratentorial Ependymoma, ZFTA fusion-positive (formerly C11orf95):
-Age
-Location
-Prognosis

Answer 9

-Infants to Adults
-Frontal or Parietal lobes
-Poor prognosis (generally)

Question 10

Posterior Fossa group A (PFA) Ependymoma:
-Mutation

Answer 10

Loss of nuclear H3 p.K28me3
-Global reduction of of K27me3 by IHC

Question 11

Posterior Fossa group A (PFA) Ependymoma:
-Age
-Location
-Prognosis

Answer 11

-Infants & Kids (median: 3 y/o)
-Roof or lateral aspect of the FOURTH ventricle
-Poor prognosis

Question 12

Posterior Fossa group B (PFB) Ependymoma:
-Molecular characteristic
-Age
-Location
-Prognosis (poor prognostic mutation)

Answer 12

-Retained nuclear expression of H3 p.K28me3
-Adults (median: 30 y/o)
-Floor of FOURTH ventricle (can occur anywhere in region of 4th ventricle)
-Good prognosis-generally (loss of 13q associated with poor outcome)

Question 13

Spinal Cord Ependymoma, MYCN-amplified:
-Histology
-Age/Sex
-Prognosis

Answer 13

-High-grade features (MVP, High Mitoses, Necrosis)
-Adults (median: 31 y/o)/M:F=1.0:1.7
-Poor prognosis w/ frequent neuraxis dissemination

Question 14

Myxopapillary Ependymoma:
-Location
-Grade
-Age/Sex

Answer 14

-Conus medullaris and filum terminale (almost exclusively)
-WHO grade 2
-Young Adults/Male predominance (~1.5:1.0)

Question 15

Myxopapillary Ependymoma:
-IHC (5)

Answer 15

GFAP
S100
CD56
CD99
AE1/AE3

*Negative for EMA and OLIG2

Question 16

Subependymoma:
-Location

Answer 16

Intraventricular-Exophytic
-Fourth ventricle (~60%)
-Lateral ventricle (~35%)

Question 17

Subependymoma:
-Histology

Answer 17

-Clusters of bland cells in fibrillary matrix
-Microcystic change
-Calcifications
-Low mitotic activity