Tumors

Question 1

What is the most common type of brain tumor?

Answer 1

Glioblastoma

Question 2

In what location is a brain tumor more likely to be found in adults/children?

Answer 2

Adults: supratentorial

Kids: infratentorial, cerebellum, brainstem

Question 3

New onset of seizure in an adult, what should you think?

Answer 3

Brain Tumor

Question 4

What is the meaning of a Grade II tumor?

Answer 4

Infiltrative, despite low proliferative potential, likely to recur

cytological atypia

Question 5

At what tumor grade must you begin Radiation/Chemo?

Answer 5

Grade III

Question 6

What are the 4 Histologic Parameters used for grading tumors?

Answer 6

• Nuclear Atypia
• Mitoses
• Microvascular Proliferation
• Necrosis

Question 7

What is a general rule regarding age and grading astrocytomas?

Answer 7

Lower age usually means a lower grade tumor

Question 8

Which tumor is often seen in the cerebellum, within the first two decades of life?

Answer 8

Pilocytic Astrocytoma

Question 9

How do Pilocytic Astrocytomas look?

Answer 9

Well-circumscribed, cystic with a mural nodule (has a nodule on the wall of the cyst)

Question 10

A biopsy of a pilocytic astrocytoma may yield what results?

Answer 10

• Hair-like cells with long bipolar processes
• rosenthal fibers
• GFAP positive

Question 11

Why do glioblastomas have poor outcomes?

Answer 11

They are infiltrative and poorly circumscribed, and thus cannot be resected

Question 12

What are the mutations involved in primary glioblastomas?

Answer 12

EGFR & PTEN

Question 13

Which secondary gene mutation for glioblastoma has a better prognosis ?

Answer 13

IDH1

Question 14

What is a common descriptor for glioblastomas?

Answer 14

contrast ring-enhancing, hypodense central necrosis

Question 15

3 Histological Hallmarks of Glioblastomas

Answer 15

1. Serpentine pattern of Necrosis
2. Pseudo-Palisading
3. Vascular/Endothelial Proliferation

Question 16

If you see the term “butterfly glioma” and “crossing the corpus callosum”, think…..

Answer 16

Glioblastoma

Question 17

Where are oligodendrogliomas primarily found?

Answer 17

Frontal Lobes

Question 18

How might an oligodendroglioma present histologically?

Answer 18

high incidence of calcification, high cellularity, and the presence of artifactual clear zones about nuclei (perinuclear halos) to produce the “Fried Egg” appearance

Question 19

Which gene mutations seen in oligodendrogliomas have a favorable outcome?

Answer 19

IDH1, IDH2, 1P19Q

Question 20

Where are Ependymomas located usually?

Answer 20

4th ventricle

*think “ependymal cells”, where are they usually located?

Question 21

What are the characteristics of ependymomas?

What is the prognosis?

Answer 21

They are discrete and exophytic in nature

Ependymomas are generally lethal lesions because of their position.

They rarely can be totally excised and are refractory to radio- and chemotherapy.

Question 22

What is the most common location of a Choroid Plexus Papilloma?

How does it present?

Answer 22

Most commonly present in the lateral ventricles, in children

These tumors produce CSF, so they present with hydrocephalus

Question 23

What is the main problem with Colloid Cysts of the 3rd ventricle?

Answer 23

obstructs the Foramen of Monro, causing Noncommunicating Hydrocephalus

seen in young adults

Question 24

Which mutation of Medulloblastoma has the worst prognosis?

Answer 24

MYC & 17(I17Q)

Question 25

What is the most common solid tumor in children?

Answer 25

**Medulloblastoma**

Question 26

Where do medulloblastomas commonly arise?

Answer 26

in the cerebellum, and frequently protrude into the 4th ventricle

Question 27

What is unique about AT/RTs?

Answer 27

They have divergent differentiation: Epithelial, mesenchymal, neuronal, and glial components

Question 28

Which patients are more likely to have primary CNS lymphoma?

Answer 28

Immunosuppressed individuals (_AIDS_ patients) linked with **EBV** or organ transplant pt

Question 29

What are we looking for histologically in CNS lymphoma?

Answer 29

CD20+ brown stain "Hooping" of cells separated by reticulin and silver stain

Question 30

What is the most common tumor in the pineal gland?

Answer 30

Germ cell tumor

Question 31

What is the most common benign tumor in the brain?

Answer 31

**Meningioma**

Question 32

What is the common histological appearance of a meningioma?

Answer 32

**Whorling** spindle-shaped cells often associated with psammoma body formation ("brain sand")

Question 33

Which tumor is often radiation-induced, and will grow through the skull and penetrate into the scalp?

Answer 33

Meningioma

Question 34

Which population is more likely to present with a meningioma?

Answer 34

**Women** These tumors have an active progesterone receptor

Question 35

Where do the majority of metastases to the brain originate from?

Answer 35

**Lungs**

Question 36

What should you do if a patient has a brain tumor?

Answer 36

Chest XR, to rule out metastatic carcinoma

Question 37

Which tumor is associated with Cowden Syndrome?

Answer 37

Dysplastic Gangliocytoma Mutation in **PTEN -\> IK3/AKT** signaling pathway

Question 38

Which tumor is associated with Li-Fraumeni Syndrome?

Answer 38

Medulloblastoma Mutation in **TP53**

Question 39

Which tumors are associated with Turcot Syndrom?

Answer 39

Medulloblastoma or Glioblastoma Mutations in **APC** or mismatch repair genes

Question 40

Which tumor is associated with Gorlin Syndrome?

Answer 40

Medulloblastoma Mutations in **PTCH** gene resulting in up-regulation of SHH pathway

Question 41

What is the inheritance pattern for Tuberous Sclerosis Complex? What are the associated genes?

Answer 41

**AD inheritance** - TSC1, Hamartin - TSC2, Tuberin

Question 42

What are some Subungal Fibromas?

Answer 42

**Shagreen Patches**: Localized Cutaneous Thickenings **Ash-Leaf Patches**: Hypopigmented Areas

Question 43

What is the difference between NF Type 1 and Type 2?

Answer 43

Type 1: **common, neurofibromas of peripheral nerves, optic nerve gliomas, present with Lisch nodule and cafe au lait spots** Type 2: **less common, bilateral schwannomas (CN VIII)**, increased **meningiomas, ependymomas**