2.4.1 Brain Tumors Flashcards
What is the important genetic marker for oligodendrogliomas?
-1p/16q deletions respond favorably to chemotherapy
Circumscribed gliomas may have what genetic mutation?
BRAF mutations
No IDH mutation
What is this an image of?
Ependyoma
What are the characteristics of a pilocytic astrocytoma?
- Benign tumor
- Most common CNS tumor in children
- Locations: cerebellum, 3rd ventricle, optic nerve
- Possibly associated with NF1
What is this an image of?
Glioblastoma Grade IV
What are the characteristics of a glioblastoma?
- Grade IV Astrocytoma
- May see defined lesion on imaging
-Butterfly effect – arising in the cerebral hemisphere and crossing the corpus callosum
What is this an image of and what are the characteristics?
- Meningeal Carcinomatosis
- Malignant, metastatic tumor cells growing in subarachnoid space
- Typically from:
- Small Cell Carcinoma
- Adenocarciomas: breast, lung
What is this an image of?
Pilocytic Astrocytoma
What are the covered parts?
What are the characteristics of hemangioblastoma?
- Highly vascular tumor typically seen in the cerebellum
- Often associated with VHL Disease:
- -AD
- -Cysts in pancreas, liver, kidneys
- -RCC & capillary hemangioblastoma
Characterized by neoplastic stromal cells and abundant small vessels
What is this an image of?
Maxopapillary ependymoma
What are these image of?
Glioblastoma
Left demonstrates necrosis
Right demonstrates vascular proliferation
What is this an image of?
Meningioma
What are the gross findings associated with brain metastases?
-sharply demarcated, gray white junction, surrounding edema
What are the characteristics of a medulloblastoma?
- Malignant tumor of childhood
- May occur in the cortex of adults due to seeding
- Tumor of granular cells of cerebellum
- Derived from neuroectodermal tissues
What is the role of IDH-1 in diffuse gliomas?
What are the characteristics of an ependyoma?
- Malignant tumor
- Commonly found in 4th ventricle of children, causing hydrocephalus
- Locations: Ventricular areas, spinal cord
What is this an image of and what are the characteristics?
Diffuse astrocytoma
MRI showing no enhancement
Malignant, high grade tumor
Most common adult primary brain tumor
WHO Grades: II, III (Anaplastic), IV (Glioblastoma)
Imaging: edema, mass effect, no well-defined lesion
What are the imaging and histological characteristics of medulloblastoma?
- Imaging: midline lesion in cerebellum
- Histology: small, round cells with Homer-Wright Rosettes
What is this an image of?
Medulloblastoma
What are the histological characteristics of a glioblastoma?
- Increased necrosis
- Pseudopalisading (living cells lined up next to areas of necrosis)
- Increased endothelial cell proliferation
- Vascular proliferation
What are the imaging and histological characteristics of a pilocytic astrocytoma?
- Imaging: cystic-solid enhancing lesion with mural nodule
- -Relative circumscription
- Hist: eosinophilic astrocytes with thick processes
- -“Rosenthal Fibers”
What are the genetics associated with diffuse astrocytoma?
What is this an image of?
Diffuse astrocytoma
What is this an image of?
Hemangioblastoma
What are these images of?
Ependymoma
What are the characteristics of CNS Lymphoma?
- Imaging: enhancing lesion in cerebellum
- Features:
- -B cells (stained via CD20)
- -EBV association
- -Angiocentric growth pattern
- -Associated with immunosuppression
-Avoid Preop steroids as some lymphomas are very sensitive
What are the two types of growth patterns of central nervous system tumors?
Diffuse (right) and discrete mass (left)
What is this an image of?
Medulloblastoma
What are the genes associated with a diffuse glioma?
IDH1 or IDH2
What is this an image of?
Oligodendroglioma
Why is there poor prognosis associated with medulloblastoma?
-Poor prognosis due to rapid growth & spread via CSF
What is this an image of and what are the characteristics?
Pleomorphic Xanthoastrocytoma
-Histology:
- -Large, bizarre cells
- -Chronic inflammation
- -Special structures: eosinophilic grnular bodies
-Imaging: superficial mass, interfacing with leptomeninges, cystic with solid nodule
What is this an image of and what are the characteristics?
Oligodendroglioma
Malignant tumor of oligodendrocytes
Histology - calcification, perinuclear haloes, chicken wire vasculature, and fried egg appearance
Usually involves the frontal lobe and can cause seizures
What is this an image of?
Pleomorphic Xanthoastrocytoma
What is this an image of?
Meningioma - psamomma bodies are present
What are these images of?
What is this an image of?
Oligodendroglioma
What is this an image of?
Meningioma
What are the most common metastasis to the brain?
- Top 5 (80% of metastatic carcinoma to the brain)
- Lung
- Breast
- Skin
- Kidney
- GI Tract
What is this an image of?
Ependyoma
What are the characteristics of a meningioma including imaging, histology, and cytogenetics?
- Benign tumor of arachnoid cells
- Typically affects females over males
- Imaging: round, extradural mass with edema
- Typically noninvasive
- May cause seizures due to compression
- Easily resected
- Histology: whorled cells, psammoma bodies
- Cytogenics: has progesterone receptor, loss of chromosome 22q
- Possibly associated with NF2
What is this an image of?
Glioblastoma
What are these images of?
Pilocytic astrocytoma - histological characteristics include ROSENTHAL FIBERS
What is this an image of?
Anaplastic Astrocytoma
WHO Grade III
A+M = Atypia and Mitosis
What is this an image of and what are the characteristics?
Atypical Teratoid Rhabdoid Tumor (ATRT)
What are the characteristic histological findings associated with ependymoma?
-Perivascular pseudorosettes, effacement with vascular tissue
What is this an image of?
Primary CNS lymphoma
What is this an image of?
Glioblastoma
What are the characteristics of Atypical Teratoid Rhabdoid Tumor?
- Tumor of rhabdoid cells affecting young children (<5)
- Location: posterior fossa or supratentorial
- Rhabdoid cells; polyphenotypic - neuroecto, epithelial, and mesenchymal
- High frequency of hSNF5/(SMARCB1)INI1 gene loss from chromosome 22
What are these images of and what are the characteristics?
Ganglioma
