Lymphomatoid granulomatosis

The patient is a 21 year old who received a kidney transplant more than 10 years ago.


Central Neurocytoma

The patient is a 20 year old with an intraventricular tumor





This patient presented in his 20s with 2 months of progressive headaches and was found to have a right cerebellar cystic mass.




Hemangioblastoma (WHO grade I): 
"Uncertain" Histogenesis

      Various cell lineages such as vascular, glial, neural, fibrohistiocytic, and smooth muscle/myofibroblastic have been proposed for the so-called stromal cells, which are thought to represent the neoplastic component of these lesions

-     Neg for endothelial markers

-     CD133, VEGF positive, Epo/EpoR coexpression'

-     GFAP positive cells may result from phagocytosis

      The VHL gene is expressed particularly in Purkinje cells of the cerebellum (mutations may be inherited or somatic).

      VHL mutation may lead to developmental arrest of angioblasts.  Pluripotent neoplastic angioblasts may be the cell of origin.

      Possible origin is 'angiomesenchyme'  which may give rise to three cell types (stromal cells, pericytes, and endothelial cells).

Clinical Features

- 25 % occur in VHL Patients, 75 % occur sporadicly

- Locations : Cerebellum , brain stem,Spinal cord, Supretentorial sites  more frequently in VHL patients

-Symptoms are associated with increased ICP, Secondary erythrocytosis secondary to EPO production

-MRI shows cystic lesion with enhancement


- Tumors consisting of numerous vessels intermixed with stromal cells

- Vessels have hyperplastic endothelial cells and pericytes

- Stromal cells have abundant lipid-rich clear cytoplasm with slight pleomorphic nuclei

-Rare mitosis

-Cyst wall may show reacive astrocytosis with Rosenthal Fibers


-Stromal cells are positive for: Vimentin,S100,Oil Red O

-Stromal cells are negative for :CD34,FVIII,CK,EMA,GFAP


-Metastatic Renal Cell CA: Non-cystic,Abundant mitosis,EMA,Vimentin and CK  positive

-Pilocytic Astrocytoma: Fibrillary astrocytes, GFAP diffusely positive

17 month old female with a cystic insular, temporal lesion

The patient is a 17 month old female with a cystic insular and temporal lobe lesion.  There is some enhancement.
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Desmoplastic infantile ganglioglioma (DIG)
- WHO grade I, glial or glioneuronal superficial tumors with prominent desmoplasia.
- Present in the first 2 years of life
- Supratentorium: Frontoparietal
- Symtoms of increased ICP
- Distinctive features include collagenized regions dominated by spindly astrocytes in fascicular or storiform array and admixed small cells of primitive appearance in nodular aggregates.
- GFAP-positive astroglial cells within the desmoplastic regions
- Synaptophysin and Neurofilament positive neuronal cells in non-collagenized areas
- Small cell populations can be positive for GFAP, Neuronal markers ( Synaptophysin, Beta-tubulin, NF, MAP-2
  • Fibrohistiocytic neoplasms
  • Intracranial fibromatosis
  • Fibroblastic meningioma
  • Fibrosarcoma


    Spinal osteogenic meningioma

    This patient had a history of worsening bilateral leg numbness and was found with neuroimaging to have an extra-medullary, intradural thoracic mass.
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    Hypoxic-Ischemic encephalopathy

    The patient was a 35 year old woman who apparently suffered a cardiac event at home.  She arrived at the hospital obtunded with minimal brainstem reflexes.  Two days after admission she developed V-fib and became completely unresponsive.  An MRI at this time showed severe anoxic changes.  She was pronounced dead 12 days after the initial event.


    This 2 year old was noted to have a head tilt for 1 week.  A well-circumscribed, enhancing lesion near the foramina of Luschka displaced the pons.

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    Meningioma with clear cell features

    The patient is a 5 year old who had a meningioma involving the cavernous sinus at age 2 1/2.  The tumor recurred within 2 years and has not responded well to radiation therapy.
    clearcellmeningi4x.jpg Thumbnail image for clearcell 20x.jpg clearcellmening40x.jpg
    Clear cell meningioma:

    • Incidence: 0.2 % of all meningiomas, rarest variant
    • WHO Grade II
    • Age: Younger patients
    • Sex:Female predilection in Ped CCMs
    • Locations: Cerebellopontine angle and Intraspinal
    • Recurrence: High rate, up to 61%

    Histology:  Solid, clear glycogen rich cells, round and innocuous nuclei, inconspicuous nucleoli,  lack mitotic activity,  distinctive hyalinised stroma.

    Immunohistochemistry:  EMA +ve,Vimentin +ve, Inhibin -ve,GFAP -ve , PAS +ve diastase sensitive material.High MIB-1 LI accounts for the high-recurrence rate.

    DDX:Differential diagnoses include microcystic meningioma, hemangioblastoma, clear cell ependymoma and metastatic carcinoma.

    References: Greenfield's Neuropathology, Sixth Edition

    1: Clear cell meningioma, an uncommon variant of meningioma: a clinicopathologic study of nine cases. J. Neurooncol. 2007 Feb;81(3):315-21.