CASE : The spinal MRI of a 22-year old male with neurofibromatosis type-2 showed a hyperintense lesion. The lesion was resected and histopathologic section is shown in image.

Question 1: What is the diagnosis?
A. Medulloblastoma
B. Ependymoma
C. Retinoblastoma
D. Central neurocytoma
Question 2: Which of the following statements is true regarding this tumor?
A. They are predominantly supratentorial
B. Posterior fossa tumors in adults have a good prognosis
C. Spinal tumors have a bad prognosis
D. IDH 1 and 2 mutations are present in 100% cases.
Question 3: Identify the variant of the tumor shown in the image below.

A. Tancytic
B. Myxopapillary
C. Subependymoma
D. Anaplastic
Question 4: Which of the following statements is true regarding tancytic ependymoma?
A. GFAP negative
B. Abundant rosettes
C. Can be confused with pilocytic astrocytoma
D. WHO Grade 1
Question 5: Identify the FALSE statement regarding the variant of ependymoma shown below

A. WHO Grade 1
B. Arises from filum terminale
C. Aggressive clinical course
D. Mucin stains positive
Question 6: TRUE statement regarding recent molecular classification (WHO CNS 2021 5th edition ) of ependymoma is
A. Spinal ependymomas with MYCN have a good prognosis
B. ZFTA Fusion- favorable prognosis
C. YAP Fusion- poor prognosis
D. Spinal ependymomas with NF 2 mutation- favorable prognosis
ANSWER- Question 1
Correct answer is B- Ependymoma
Ependymomas are characterized by perivascular rosettes and ependymal rosettes which have an empty central lumen

ANSWER- Question 2
CORRECT ANSWER IS B
🐱 Majority of of Ependymomas are infratentorial.
🐱Posterior fossa tumors in children have a poor prognosis (PF-A)- associated with loss of H3K27me, whereas Posterior fossa tumors in adults have a god prognosis (PF-B)- H3K27me is retained.
🐱 Spinal ependymomas have a good prognosis, whereas a small number of ependymomas associated with MYCN have a poor outcome.
🐱IDH 1 and 2 are associated with astroctyomas and oligodendroglomas but nor ependymomas.
ANSWER-Question 3
CORRECT ANSWER IS A
Diagnosis is TANCYTIC EPENDYMOMA, 🐱 Tancytes are cells with fibrillary processes which line ventricles along with ependymal cells.

ANSWER - Question 4
Correct They are GFAP positive 🐱Confused with pilocytic astrocytoma because of the prominent fibrillary projections 🐱It is a GRADE II Ependymoma 🐱 Ependymal rosettes and pseudorosettes are scanty in tanytic ependymoma, which makes diagnosis challenging.
ANSWER- Question 5
Correct answer is C
💀Diagnosis is myxopapillary ependymoma
💀It is a Grade II Tumor according to latest WHO
💀It is common in adults and arises from the filum terminale
💀It is clinically indolent ( nor aggressive)
💀Stains for Mucin is positive.

ANSWER - Question 6
Correct answer is D
Spinal ependymomas with NF2 mutation has a good prognosis
Summary of latest molecular updates in ependymoma
https://www.pinterest.com/pin/1140114461888911764/sent/?invite_code=8c0c292164cb49309c55337a1d93b1a7&sender=1140114599324959776&sfo=1