Pathology Lab-CNS I Flashcards
55-year-old man presented one year ago with headaches for which no cause could be found. Just before his death he developed signs of increased intracranial pressure. A left frontal mass was noted on MRI. Gross section of his brain is shown below. What is your diagnosis?
Note that there is an expanding white matter mass that is flattening the gyri from increased intracranial pressure. Also note the diffuse infiltration and lack of borders. The gross image is characteristic of astrocytomas.
A seven-year-old boy was noted to be hyperactive with an increasingly poor performance in school. He complained of dull, generalized headaches, particularly in the morning, which seem to be relieved when standing or after vomiting. Physical exam reveals bilateral papilledema. An MRI was performed and a cystic lesion with a mural nodule was resected from the left temporal lobe. Histological analysis would reveal what grade of a tumor?
Grade I. The only scary thing it has is vascular proliferation. These tumors tend to be well circumscribed, low cellularity and no necrosis. Note that these tumors are often found in the cerebellum.
A 50-year-old man admitted to the hospital for sudden onset of a grand mal seizure died after repeated episodes of loss of consciousness. He gave a 3-month history of headaches and complaining of continuously sensing a poorly defined “strange smell.” CAT scan disclosed a large irregular frontal lobe mass with ring enhancement. A few days later he died and his autopsy is shown below. What is your diagnosis?
Note all of the hemorrhage and necrosis in the white matter. This is a glioblastoma.
A 47-year-old woman presented with a 2-month history of increasingly severe headaches. A brain scan revealed a 2 cm round, nodular tumor attached to the dura in the right fronto-parietal region. The tumor was successfully excised and pathological examination is shown below. Will this patient be happy about their diagnosis?
Yes. Note the psammoma bodies (calcified tumor cells)Most meningiomas are grade I encapsulated benign masses.
A 19-year-old male enlistee in boot-camp presents with fever, headache, stiff neck and mild stupor. Physical exam reveals Kernig’s and Brudzinski’s signs. Lumbar puncture showed elevated opening pressure; yellowish and cloudy CSF; elevated polys and protein and decreased glucose. Gram stain of sediment shows bacteria. What would his CSF look like if this were viral meningitis? What if it were tubercular meningitis?
Viral = lymphocytes and all other values are normal. Tubercular = lymphocytes with similar CSF values as this patient.
What is the most common primary brain tumor in adults?
Glioblastoma Multiforme
What tumors are prevalent in kids?
Astrocytoma, Primitive neuroectodermal tumor, Ependymoma and Craniopharyngioma
Where are most brain tumors located in kids?
Posterior cranial fossa and infratentorially
A young girl is diagnosed with a medulloblastoma. What imaging manifestation, other than a mass, would indicate this?
Hydrocephalus from blockade
Why do ependymomas have such a poor prognosis?
They are located right in the ventricles and can seed the entire ventricular space via the CSF
What clinical symptoms do patients with cerebellar tumors often present with?
Ataxia, double vision and nystagmus
What makes astrocytomas so difficult to cure?
It is an expansile mass with poorly defined borders.
How do you separate a glioblastoma from an astrocytoma? What grade is the image seen below?
Glioblastomas are grade IV astrocytomas. Grade IV tumors have mitoses, necrosis and angiogenesis. This is a grade III astorcytoma. Note high cellularity and mitoses.
What type of astrocytoma is seen below?
Note the cysts and lack of cellularity, this is a grade I astrocytoma (Pilocytic astrocytoma)
What genetic alterations are associated with astrocytomas?
Low grade: p53 & PDGF-A. Higher grade: RB, p16 Glioblastoma: p53 & EGFR
Where are pilocytic astrocytomas often located?
Optic nerve, third ventricle and cerebellum.
What is the structure indicated below typically found in?
This is a Rosenthal fiber. Note the loose edematous tissue with elongated fibers.
A seven-year-old boy was noted to be hyperactive with an increasingly poor performance in school. He complained of dull, generalized headaches, particularly in the morning, which seem to be relieved when standing or after vomiting. Physical exam reveals bilateral papilledema. MRI showed a lesion in the posterior fossa. Biopsy of a brain tumor is shown below. What is your diagnosis?
Notice the sheets of neural tumors with very little cytoplasm. This is a medulloblastoma.
What are other neural cell tumors? What structure can you see in these?
Neuroblastoma, Ewing sarcoma, Small-cell carcinoma, Medulloblastoma and PNET. Homer-Wright rosettes (with pink fibrillary center) are present in these tumors.
A 60-year-old man presented with headaches, deteriorating vision and periodic loss of consciousness; suddenly developed left hemiplegia, fixed and dilated pupils and died shortly afterwards. Autopsy is shown below. What would you expect to see on histological analysis of this tumor?
This is a glioblastoma. Note the extensive hemorrhage, gyral flattening and necrosis. Histologically you would see coagulative necrosis surrounded by palisading small cells (pseudo-palisading or serpentine necrosis). Also note endothelial cell proliferation due to angiogenesis and VEGF stimulation.
What terminal event is shown below as a consequence of intracerebral pressure?
Uncal herniation
What drug might you research for clinical management of glioblastomas?
VEGF. This feeds the tumor and gives it blood supply and blocking it may reduce tumor growth and survival.
What low-grade white matter tumors are often found in the cerebral hemispheres in adults?
Oligodendromyoma
What is the most common site for a meningioma?
Parasaggital sinus
Mutation of what gene is associated with the tumor seen below?
This is a meningioma. You see multiple meningiomas in people with NF-2 mutations, which expresses the merlin protein.
What is Kernig’s sign?
*
What is Brudzinski’s sign?
*
Where are neutrophils found when a patient has bacterial meningitis?
Sub-arachnoid space
What are the main causes of bacterial meningitis in neonates?
Group B Strep, E. Coli and Listeria
What are the main causes of bacterial meningitis in kids?
Neisseria M. and Strep Pneumoniae
What are the main causes of bacterial meningitis in elderly?
Strep Pneumoniae and Listeria
What type of people are most likely to come down with bacterial meningitis?
Asplenic patients, immunocompromised patients, trauma, septicemia and local infections
