Path I Flashcards
Group atrophy of skeletal muscles suggests what cause?
neurogenic disease
Perifascicular atrophy of skeletal muscle suggests what cause?
dematomyositis
Type II fiber atrophy of skeletal muscle suggests what cause?
corticosteroid therapy or disuse
Whta pathology is shown in the provided image?
Denervation & atrophy
some of the cells are very atrophic & more angulated
not dead - just atrophic b/c not getting the stimulation from the nerve
During reinnervation, what can happen to fiber type?
they can switch depending on what type of nerve the get re-innervated by
axon determine what type o myofibril you have
What type of pathology is shown in teh provided iamge?
How do you know?
Group atrophy & then regenration separated by type
- loss of “checkerboard” appearance to fiber type
What condition is seen in this provided image?
Myofiber hypertophy
can have many causes
What is the difference in presentation between Duchenne muscular dystrophy & Becker muscular dystrophy?
Presence of dystrophin?
- Duchenne
- severe chronic muslce damage
- dystrophin absent (frameshift)
- Becker
- milder chronic muscle damage
- dystrophin reduced (truncation)
What is the inheritance pattern of Muscular dysrophy with dystrohin mutation?
X-linked
(Duchenne & Becker)
Dystrophin is encoded by what gene?
IHC
If this is a stain for dystophin, what condition is depicted in the provided slide?
Duchenne muscular dystrophy
the brown outline of the myofibers in the right-hand box is the dystrophin; notice this is absent in the larger image, indicative of the absence of dystrphin
What condition is depicted in the provided slide?
The sample on the left is froma 3 yr old and the sample on the right is from a 9 yr old
Muscular Dystrophy
The collagen fibrosis that course between & around the myofibers is characteristic of muscular dystrophy
In the sample on the right, even more myofibers have been replaced by collagen & adipose
Identify the types of peripheral nerve damage shown in the diagram
- Top: axonal degeneration
- significant atrophy of myofibers
- Bottom: demyelination
- no signifiant atrophy of myofibers
- transmission will slow
What are the characteristics of nerves after regeration of axons after injury?
What are the characteristics of nerves after remission of demyelinating disease?
- Axon injury
- connections with myofibers reform
- new internodes are shorter
- sheaths are thinner
- Demyelinating
- remyelination
- new internodes are shorter
- thinner myelins sheaths than the undamaged nodes
What types of tumors have evidence of Schwann cell differentiation?
Peripheral Nerve Sheath Tumos
Peripheral nerve sheath tumors are associated with what common familial tumor syndromes?
neurofibromatosis 1 & 2
schwanomatosis
How do malignant peripheral nerve sheath tumors most commonly arise?
malignant transformation of preexisting benign plexiform neurofibromas
What pathology is shown on the provided image?
Benign or malignatn?
Arising from what cells?
Schwannoma
(well-circumscribed, encapsulated, firm gray masses, loosely attached to, but not invadign associated nerve)
benign tumor
often arist directly from peripheral nerves
Schwannomas asre associated with what gene mutation?
inactivating mutation in NF2 gene on chromosome 22
wiht loss of gene product (merlin)
The provided microscopic samples are from what larger pathology? Describe the two samples.
Schwannoma
- Left
-
Verocay bodies (arrow) in Antoni A areas
- tumor cells are very elongated & somewhat spindle-shaped
- sometimes lined up like a picket fence & in between them will look like a little pathway that has been cleared
-
Verocay bodies (arrow) in Antoni A areas
- Right
- Cellular Antoni B region (left) and loose Antoni A (right)
- think “B for Barren”
What is the composition of neurofibromas?
schwann cells are admixed with perineurial-like cells, fibroblasts, mast cells & CD34+ spindle cells
What are the 3 types of neurofibromas?
superficial cutaneous
diffuse
plexiform
Neurofibromas can be associated with what gene mutation?
NFT1
What pathology is shown on the provided image?
Cutaneous superficial neurofibroma
ovoid or fusiformmass with gelatinous or wavy cut surface
(transected nerve fibers can be seen at the ends)
The provided microscopic sample is from what pathology?
Neurofibroma
small, elongated spindle cellw & collagenous stroma
What pathology is shown in the provided image?
Plediform Neurofibromas
“bag of worms”
The provided cross section sample is take from what pathology?
fascicles of plexiform neurofibroma
What is a feature of plexiform neurofibromas that is very rarely seen on other types of neurofibromas?
“shredded carrots” collagen bundles
What pathology is shown in the provided images?
Malignant Peripheral Nerve Sheath Tumor
large, fusiform masses arising from & incorporating nerves
bulky, circumscribed, pseudo-encapsulated mass w/ hemorrhage (black curved arrow) & cystic areas (blue arrow)
The provided microscopic images are from what larger pathology?
Malignant Peripheral Nerve Sheath Tumor
higih-grade, cellular neoplasm with numerous mitoses & some nuclear atypia
Right - focal area of nerosis indicated by black curved arrow
How often do primary CNS tumors metastasize outside of the CNS?
very rarely
What are the most common CNS tumors in adults?
glioblastoma
meningioma
ependyoma
What are the most common CNS tumors in children?
cystic (pilocystic) astrocytoma
medulloblastoma
brainstem glioma
Compare / contrast the following features for CNS tumors in adults & children:
Supra vs. infratentorial?
prevalence
- adult
- 70% supratentorial
- not in top 10
- children
- 70% infratentorial
- 2nd most common general type of cancer
What are the risk factors for developing a CNS tumor?
- Turcot Syndrome
- Neurofibromatosis
- Type 1
- Type 2
- Cigarette smoking
What pathologies are associted with Turcot syndrome?
multiple adenomatous colon polyps
brain tumors
What pathologies are associted with Neurofibromatosis Type 1?
- neurofibromas
- MPNSTs
- optic nerve gliomas
- other glial tumors
- pheochromocytomas
What pathologies are associted with Neurofibromatosis Type 2?
- bilateral 8th nerve schwannomas
- mulitple meningiomas
- ependymomas of spinal cord
What are the categories of giomas?
astrocytoma
oligodendrogliomas
ependymomas
Identify the following characteristics for Pilocytic Astrocytoma:
Benign vs malignant
demographics affected
location
grade
- relatively benigh
- children & young adults
- cerebellum
- grade I
- grow very slow
What pathology is depicted in the provided image?
Pilocytic Astrocytoma
cystic & solid part located in the cerebellum
What pathology is depicted in the provided image?
Pilocytic Astrocytoma
cystic & solid part located in the cerebellum
The provided microscopic slides are a sample from what pathology?
Pilocytic Astrocytoma
- Left
- biphasic patter w/ loose, myxoid areas ademixed w/ eosinophilic compact regions
- Right
- rosenthal fibers are eosinophilic, irregulat, elongated “corkscrew” protein aggregates
Identify the following characteristics for Diffuse Astrocytoma:
demographics affected
grade
grade II
young - middle aged adults
What pathology is shown in the provided images?
Diffuse Astrocytoma
infiltrative margins
left : right frontal tumor w/ expanded gyri & flattening
right: bilateral expansion of septum pellucidum
What features would you expect to see in a microscopic sample from a Diffuse Astrocytoma?
- subtle
- some nuclear pleomorphism
- increased cellularity
- GFAP
Anaplastic Astrocytom is what WHO grade?
III
What features would you expect to see in a microscopic sample from a Anaplastic Astrocytoma?
What features will you NOT see?
- more pleomorphism
- higher cellularity
- higher mitotic rate
than Diffuse Astrocytoma
- NO necrosis
- NO vascular proliferation
What pathology is shown in the provided image?
Glioblastoma
necrotic, granular-looking, hemorrhagic
Glioblastoma is what WHO grade?
IV
Glioblastomas can cause what complications?
mass effect
herniation
What features would you expect to see on a microscompic sample of a glioblastoma?
- increased cellularity
- increased mitotic features
- increaed nuclear pleomorphism
- areas of necrosis w/ pallisading cells around the necrosis
- vascular proliferation
The provided microscopic sample of from what pathology?
Glioblastoma
necrosis w/ palisading cells is characteristic
What glioblastoma feature is shown in the provided microscopic sample?
glomeruloid body
small-type vascular proliferation
Identify the following characteristics for Oligodendroglioma:
demographics affected
location
grade
4th - 5th decade
cerebral hemispheres
grade II
What is the mutation associated with oligodendrogliomas?
Is this seen in adult or pediatric populations?
1p19q deletion, due to unbalanced translocation t(1;19)(q10;p10)
adult cases
What grade is anaplastic oligodendrogliomas?
grade III
What pathology is shown in the provided image?
Oligodendroglioma
curvilinea calcifications
What microscopic features would you expect to see in a sample of an oligodendrioma?
“fried egg” appearance & delicat meshwork of capillaries
Where are ependyomas found in children vs. adults?
Clinical features?
Which demographic has a better prognosis?
- children
- 4th ventricle
- hydrocephalus if in posterior fossa b/c destruction of 4th ventricle
- unfavorable diagnosis
- 4th ventricle
- adults (4th decade)
- spinal cord (lumbosacral)
- favorable diagnosis
CSF dissemination is common
Ependymoma is frequently seen in the setting of what condition?
neurofibromatosis type 2
What type of tumor is this tumor of the 4th ventricle?
Ependymoma
What would you expect to see in a microscopic sample of an ependymoma?
perivascular pseudorosettes (solid blue arrow)
true rosettes (open blue arrow)
What does “embryonal” indicate in the context of CNS tumors?
poorly differentiated
What is the key embryonal tumor?
medulloblastoma
Identify the characteristic of a medulloblastoma:
demographics
location
clinical features
treatment
-
demographics
- children (5-10 yr)
-
location
- exclusively cerebellum
-
clinical features
- rapid growth - hydrocephalus
- dissemination through CSF
- metastases to cauda equina
-
treatment
- highly malignant; exquisitely radiosensitive
What pathology is shown in the provided image?
medulloblastoma
destroying superior midline cerebellum
What features would you expect to see in a microscopic sample of a medulloblastoma?
sheets of small cells with elongated nuclei & scant cytoplasm
Meningioma is derived from what cells?
demographics?
grade?
location?
- mengiothelial cells
- adults - F
- grade I
- attached to dura
Meningiomas are associated with what mutations & disorders?
loss of entire chromosome 22 or 22q
neurofibromatosis type 2
What pathology is shown in the provided image?
Meningioma
well circumscribed mass attached to meninges, not invading brain parenchyma
What would you expect to see in a microscopic sample from the various variants of a meningioma?
left - psammoma bodies (some variants)
middle - Washed out nuclei & pseudo inclusions
right - whorls of cells & lobules (transitional variant)
What are the most common primary site for metastatic CNS tumor?
typical location of metastisis?
- Primary site
- lung
- breast
- melanoma
- kidney
- colorectal
- gray-white junction of cerebral hemisphere
Which primary sites can cause meningeal carcinomatosis?
lung & breast
