Malformations & Neoplasms - ExpertPath

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Answer 1

Venous Angioma

*Near lateral ventricle is the MC location

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Answer 2

Cavernoma

*Both AVMs and cavernomas can have venous angioma-like collections of hyalinized veins at the edge of the lesion

Question 3

SMA IHC

Answer 3

Angioleiomyoma of Dura

*SMA highlights numerous veins that compose this “knot-like”, rare vascular lesion

Question 4

SMA IHC

Answer 4

Angioleiomyomas are usually encountered as benign cutaneous or soft tissue lesions, but can rarely occur in the CNS, most often in the dura or cavernous sinuses. They are composed of varying sizes with abundant intervening smooth muscle

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Answer 5

Masson Tumor - papillary architecture

*shows the abundant organizing coagulum from repetitive bleeds undergoing recanalization that produces multiple vascular spaces, and papillary-like exuberant reorganization of the clot

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Answer 6

Masson Tumor - endothelial hyperplasia

*Endothelial cells in the papillary-like areas of a Masson tumor show nuclear enlargement, focal nucleoli , and mitoses . In surgically resected specimens. The underlying lesion responsible for the repetitive bleeding should be diligently sought.

Question 7

Answer 7

Masson Tumor - Extramedulary hematopoeisis

*Extramedullary hematopoiesis can occur in any organizing clot, such as subdural hematomas or Masson tumor, as seen here. This is not the cause of the underlying bleeding in a Masson tumor, it is a result

Question 8

Answer 8

Labrune Disease (Leukoencephalopathy with calcifications and cysts; LCC))

*This axial MR from a patient with Labrune disease shows a large cyst and diffuse bilateral white matter damage . The latter accounts for the alternate name for the condition, leukoencephalopathy with calcifications and cysts (LCC).

Question 9

Answer 9

Labrune Disease (Leukoencephalopathy with calcifications and cysts; LCC))

*Calcifications are characteristic of Labrune disease and are reflected in the alternate name, LCC. Note the calcifications , hemosiderin , and gliosis in this example

Question 10

Answer 10

Labrune Disease (Leukoencephalopathy with calcifications and cysts; LCC)

*Autosomal RECESSIVE disorder - Children/Young adults presentation

• The disease is characterized by the features in its name, as well as hyalinized small vessels and often fibrinous exudates secondary to vessel damage.

Question 11

Answer 11

Labrune Disease (Leukoencephalopathy with calcifications and cysts; LCC)

*Rosenthal fibers are typical of chronic gliosis and some low-grade gliomas and can be quite conspicuous in gliotic areas in Labrune disease. They should not prompt a diagnosis of pilocytic astrocytoma.

Question 12

Answer 12

Labrune Disease (Leukoencephalopathy with calcifications and cysts; LCC)

*Fibrinoid exudate and fibrinoid vascular necrosis can be found in biopsies of LCC; this should not be misinterpreted as radiation necrosis.

Question 13

Question 14

Answer 14

Venous Angioma

*This venous angioma is an incidental finding; it is composed of a loose aggregate of slightly dilated veins of varying calibers and located near the cortical gray-white junction.

Question 15

Answer 15

Venous Angioma

*Occasional lesions are more compact than the usual venous angioma, but composed of normal veins, not the hyalinized vessels of a cavernoma. As with the classic dispersed venous angiomas, these difficult-to-classify lesions are unassociated with hemosiderin deposition.

Question 16

Answer 16

Venous angiomas are composed of dilated, patent delicate veins separated by expanses of normal intervening brain parenchyma. Note the absence of blood products or rarefaction of the interspersed white matter.

Question 17

Answer 17

Telangiectases

• Most common in the pons, specifically the base . There is no mass effect, hemorrhage, or surrounding hemosiderin staining in these lesions that are most always asymptomatic incidental findings, whether radiologic or pathologic (post mortem).

Question 18

Answer 18

Telengiectasia

*The capillary aggregates in a telangiectasia are apparent at low magnification. Note the margination of white blood cells in these lesions ; this is incidental.

Question 19

Answer 19

Telangiectasia

*Intervening parenchyma, here with large neurons, is free of gliosis and hemosiderin staining. This lumen contains protein strands and stars, a common incidental finding post mortem

Question 20

Answer 20

Venous Angioma

*Other than dilatation, component veins of a venous angioma are unremarkable. They may contain protein strands (protein threads) that should not be mistaken for fungi. Protein threads lack the homogeneity of size and shape expected of infectious organisms.

Question 21

Answer 21

Telangiectasia

*This incidental telangiectasia produces a blush of discoloration in the pons that can be misinterpreted as pontine hemorrhage or artifact.

Question 22

Answer 22

Telangiectasias are aggregates of thin-walled, generally uniform, delicate vessels. Normal parenchyma is interspersed between the vessels and is devoid of hemosiderin pigment or gliosis. Note the preservation of basis pontis neurons. Neutrophils within vessels represent margination, not vasculitis.

Question 23

Answer 23

Compare the cortex containing a telangiectasia with its innumerable delicate capillaries to adjacent normal cortex with normal vascular density

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Trichrome

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CD34

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Trichrome

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Whole Mount - Trichrome

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