CNS Pathology case based MCQs-1

Case: A 12- year old boy presents with headache , projectile vomiting and blurry vision. CT scan shows a posterior fossa mass lesion. Histopathologic image of the resected section is seen below.

CNS Pathology case based  MCQs-1

Answer the questions based on this case

Question 1: Which of the following genetic alterations has the BEST prognosis in this tumor?

A. WNT-activation
B. SHH- activation, TP53 wildtype
C. NMYC-amplification
D. SHH- amplification, TP53 mutated

Question 2: Identify the false statement regarding this tumor.

A. Associated with turcot syndrome
B. Extremely radiosensitive
C. WHO Grade 3
D. TP53 mutation is associated with a bad prognosis

Question 3: Most common cytogenetic abnormality associated with this tumor is?

A. Isochromosome 17q
B. Monosomy 6
C. Isochromosome 12p
D. Balanced translocations

DIAGNOSIS

Diagnosis is medulloblastoma

ANSWERQuestion 1

Correct answer is A: WNT-activated medulloblastomas have the best prognosis among all.

SHH- amplification, TP53 mutated medulloblasyomas have a bad prognosis.

ANSWER Question 2

Correct answer is C
🍉Medulloblastoma is WHO Grade 4
🍉Syndromes associated with medulloblastoma- Gorlin syndrome, Turcot syndrome
🍉It is a radiosensitive tumor.
🍉Isochromosome 17q is association with a bad prognosis.

ANSWER Question 3

Correct answer is A

Most common cytogenetic abnormality in medulloblastoma is isochromosome 17 q

WNT-activated medulloblastomas are associated with monosomy 6 and have a better prognosis.