CNS Tumors Flashcards
Diffuse Astrocytoma
Rosenthal Fiber
What tumor type are Rosenthal Fibers associated with?
Pilocytic Astrocytoma
Glomeruloid Tufts (in Glioblastoma)
Eosinophilic Granular Body, found in cystic areas of pilocytic, astrocytoma
Cystic cerebellar lesion with a contrast-enhancing mural nodule (Pilocytic Astrocytoma)
Necrotic Glioblastoma
Rosenthal fiber
Pilocytic Astrocytoma - compact and spongy parts
Gemistocytic Variant of Diffuse Astrocytoma
Anaplastic Astrocytoma
Oligodendroglioma
Distinctive features of these glial-derived tumors include round, regularly appearing neoplastic cells without obvious cytoplasmic processing. Note the presence of small, branching, delicate capillary processes in the background. These are so-called “chicken wire capillaries.” Interspersed between tumor cells are small, reactive astrocytes, which are recognizable due to their fine, eosinophilic, cytoplasmic processes.
Oligodendroglioma, Chicken-wire capillaries
Oligodendroglioma with chicken wire capillaries
Green: neuron – prominent nucleolus, large nuclei
Blue: oligodendrocyte – round nuclei, compact chromatin, barely any cytoplasm
Light blue: astrocyte – oval to elongated nuclei, open chromatin, scant prominent eosinophilic cytoplasm
Ependymoma With Rosettes and Canals
Normal Ependymal Lining
Ependymoma
Pilocytic Astrocytoma (from wikipedia)
Perivascular pseudorosette
This rosette consists of tumor cells collected around a blood vessel. It’s called a pseudorosette because the central structure isn’t part of the tumor. In the past, the term pseudorosette meant any rosette that didn’t have a truly empty lumen…but it seems that designation is kind of outdated. These rosettes are common in ependymomas, but you also see them in medulloblastoma, PNET, central neurocytomas, and glioblastomas.
True Rosette
This rosette (seen in ependymoma) consists of tumor cells surrounding an empty lumen. It is thought that these structures represent attempts by the tumor cells to recreate little ventricles with ependymal lining. One thing to note: although these guys are characteristic of ependymoma, they’re not seen in every case. In fact, it’s fairly uncommon to find them at all (they’re only present in a small percentage of well-differentiated ependymoma).
Perivascular pseudorosette, Ependymoma
Homer Wright Rosette
This rosette, named for James Homer Wright, the first director of the Massachusetts General Hospital, is typically seen in neuroblastomas, medulloblastomas, and primitive neuroectodermal tumors (PNETs). It consists of a halo of tumor cells surrounding a central region containing neuropil (hence its association with tumors of neuronal origin).
Medulloblastoma
Medulloblastoma
Medulloblastoma
Medulloblastoma
Medulloblastoma
Medulloblastoma, with Homer Wright Rosettes
Medulloblastoma, Neurofilament protein used to detect differentiation
What tumor type(s) are Homer Wright Rosettes associated with?
neuroblastomas, medulloblastomas, and primitive neuroectodermal tumors (PNETs)
What tumor type is “chicken wire” associated with?
Oligodendroglioma - goes along with “fried eggs”
Difference between neurofibroma and Schwannoma?
The neurofibroma incorporates axons, while the Schwannoma displaces normal elements of the nerve to one side.
Bilateral acoustic/vestibular Schwannoma = ?
Neurofibromatosis Type II
Multiple neurofibromas is probably…
Neurofibromatosis type 1
Multiple Neurofibromas, NF1
Multiple Neurofibromas, NF1
Multiple Ring Enhancing Lesions Due to Metastatic Cancer
Transitional Meningioma, with whorls and cords of neoplastic cells
GBM, EGFR Stain
Glioblastoma characteristically expresses EGFR (a membrane protein) strongly when there is EGFR genetic amplification. Again, positive staining appears brown. Based on this, as well as other later molecular changes, GBMs can be classified on a molecular basis as primary or secondary.
GBM, p53 Stain
Glioblastoma usually does not show a strong expression of p53 (a nuclear protein). A positive stain would label the nuclei brown, this is a negative stain with the nuclei stained in blue (hematoxylin is used as a counterstain).
Psammomatus Meningioma, contains Psammoma bodies
Fibrous Meningioma
Age distribution of brain tumors?
Bimodal - first peak incidence in children < 5, second peak in adults 45-70
Most common tumors in children ages 0-4? (#1 and 2)
- Embryonal/primitive/medulloblastoma
- Pilocytic astrocytoma
Most common tumors in children age 5-14?
Most common (2) tumors in adults >45?
- Meningioma
- Glioblastoma
What are the two most common (in general) types of cancer in children under 15?
- Leukemia
- Primary CNS neoplasm
Do gliomas and embryonal tumors occur more frequently in males or females?
Males
Do meningiomas occur more frequently in males or females?
Females
True or false: most primary brain tumors have a known etiology
False - most of them are sporadic, etiology unknown
Neoplasm associated with Tuberous sclerosis?
Subependymal giant cell astrocytoma
True or false: primary CNS lymphomas are associated with immunodeficiency?
True
What is the sole environmental factor clearly associated with increased tumor risk?
Irradiation (causes meningioma and astrocytoma/neuroepithelial tumors in ALL kids)
Gorlin syndrome = what type of tumor?
Medulloblastoma
Li-Fraumeni syndrome = what type of tumor?
Glioma
NF1 = what tumors?
- Neurofibroma
- Malignant nerve sheath tumor
- Optic nerve astrocytoma
- Meningioma
NF2 = what tumors?
- Schwannoma
- Meningioma
- Ependymoma
Four signs/symptoms related to tumor location?
- Epilepsy
- Focal neurological deficit
- Mental changes
- Obstructive hydrocephalus = headache
4 signs of raised intracranial pressure
- Headache (particularly postural and nocturnal or early morning)
- Vomiting (esp kids)
- Papilledema
- Clouding of consciousness and coma
5 Herniation sites?
- Tonsillar herniation (cerebellar tonsils thru foramen magnum)
- Superior cerebellar herniation (cerebellum up thru the tentorium)
- Subfalcine herniation (cingulate gyrus beneath falx cerebri)
- Transtentorial herniation of the parahippocampal gyri - also uncal herniation - temporal lobe herniates across the tentorium cerebelli
- Bilateral transtentorial or diencephalic - diencephalon herniates thru the tentorium cerebelli
This is an example of what kind of herniation
External herniation
This is an example of what kind of herniation
Tonsillar
This is an example of what kind of hemorrhage
Duret Hemorrhage, secondary to transtentorial hernaition and stretching/tearing of brainstem vasculature
A 43-year-old man has a superficial oligodendroglioma on the left frontal lobe with infiltration of the cortex. The most likely presenting symptoms are:
A. Ataxia and dysmetria
B. Mental status changes with symptoms of schizophrenia
C. Epileptiform fits
D. Loss of vision
C - the tumor is too superficial to cause B.
What type of herniation
Parahippocampal
Small areas of bleeding in the ventral and paramedian parts of the upper brainstem, (midbrain and pons), secondary to raised intracranial pressure with formation of a transtentorial pressure cone involving the cerebral peduncles (crus cerebri) and other midbrain structures caused by raised pressure above the tentorium.
Duret Hemorrhage
Cerebral peduncle indentation associated with some forms of transtentorial herniation (uncal herniation). It is a secondary condition caused by a primary injury on the opposite hemisphere of the brain.
Kernohan’s notch
Glioblastoma
Glioblastoma, Proliferative Blood Vessels
Glioblastoma on medium power. Note on the right an area of fresh hemorrhage. On the center and left, tufts of small vessels represent glomeruloid endothelial proliferation, which are due to the formation of new microvasculature. Note that there are several layers of endothelial cells surrounding each lumen, signifying abnormal endothelial growth.
Pseudopalisading necrosis, Wikipedia
Compared to normal white matter, this GBM demonstrates diffuse infiltration of neoplastic cells along white matter fascicles. Note the presence of numerous mitoses.
Does GBM stain for Ki-67?
Yes, strongly
What does GFAP stain?
Is GFAP stain found in GBM?
Astrocytes; Yes, positive GFAP will confirm the cells’ origin as astrocytes and the histological diagnosis of GBM.
Does primary GBM stain for p53?
Does primary GBM stain for EGFR?
No
Yes, if there is EGFR amplification
Does secondary GBM stain for p53?
Does secondary GBM stain for EGFR?
Yes, and IDH1
not so much
Is primary or secondary GBM associated with patients over 45?
Primary
Metastatic lung adenocarcinoma
Metastatic Adenocarcinoma (High Power) Papillary epithelial differentiation is well demonstrated in this example: epithelial cells are lining fibrovascular cores. Note also the presence of mucin-filled goblet cells with blue-gray cytoplasm.
Metastatic Adenocarcinoma, TTF stain
This stain marks a transcription factor seen in lung adenocarcinomas. Note that the nuclei stain darkly brown.
