Pathology Associates Of Lexington, P.A.
Pathology Associates Of Lexington, P.A.
Pathology Associates Of Lexington, P.A.
 Home | Pathology Group MembersOur Hospital  Search This Website:
         Anatomic Pathology
Neurological Anatomic Pathology
  • Medical disease:
    1. demyelinating disorders:
      • central: histiocytes are a marker, the Creutzfeldt cell (enlarged degenerating histiocytic cell with abnormal "starburst" mitosis) being an eyecatching enlarged & degenerating one (if seen on FS, be very cautious of diagnosing malignancy...a recent great example [T07-17] was in tissue surrounding a GBM).
      • cord & peripheral:
        1. transverse myelitis: a positive surgical biopsy shows foam cell (CD68+) and/or vacuolated neural change [LMC-03-2377]
    2. Alzheimer's:
  • Pseudotumor/neoplastic diseases:
    1. pseudotumors:
      • leptomeningeal or arachnoid cyst1: we would see as a specimen from "spinal stenosis" or "nerve entrapment" surgery [LMC-04-1850] or intracranial [LMC-05-6048]; it is a loculated accumulation of CSF & enclosed/organized by fibro-connective tissue and may be circumscribed by adhesions traversing the subarachnoid space.  Can lead to a punched out boney defect remindful radiographically of myeloma.  At spinal level most are said to be meningeal diverticulae that organize; extradural lesions in association with posterior spinal nerve roots are called "Tarlov's perineurial cyst".
      • pseudomeningocele, post-operative: If only an isolated extra-spinal pocket of CSF, it is non-communicating with the general CNS CSF space and seems just like a post-operative seroma. If it is openly "communicating", then patients tend to get headache when they assume an upright position. If cystic area has stabilized or it is only occassionally communicating via a biological ball-valve mechanism, headaches may be scarce & of brief duration. The trapped CSF has very low protein.
      • synovial (ganglion) cyst: arises from any axial site with synovium (facet, etc.).
      • simple gliotic cyst: no special lining & in middle-age to elderly adults
      • cystic lesion of multiple sclerosis (MS): very rare situation; basically a cystically degenerated demyelinating plaque [L07-11303...23 y/o F presented with facial paresis & found multiple cysts, the largest 2.8cm].
      • occult radiation necrosis: example...s/p radiation of SCC of scalp [L07-10762].
      • colloid cyst: usually antero-superior 3rd ventricle.
      • Rathke pouch cyst: similar to colloid cyst but contains squamous metaplasia.
      • intraspinal cyst: from incomplete embryonic separation of endodermal and notochordal elements ("neurenteric cyst", "foregut cyst", "enterogenous cyst", "teratomatous cyst") and has an intradural location.
      • epidermoid cyst:
      • dermoid cyst:
      • glioependymal cyst: usually paraventricular & lined by mature-appearing ependymocytes.
      • abscess: biopsy can have polys, macrophages and reactive glial cells.
      • infarct: biopsy can have polys, macrophages and reactive glial cells.
    2. neoplasia:
    • benign:
      1. meningioma: likelihood of recurring increases if Ki67 greater than 5%, PR is negative, and tumor micro-insinuates in paravascular spaces into brain. But, oncologists & neurosurgeons unlikely to do anything until recurrence unless frankly malignant histfology [T07-18]2. There is a rare sudden death seen when adjacent brain swells relative to a tumor [FA09-89, 5 cm diameter, 60 grams, beneath temp. lobe]
      2. ependymoma: a benign subcentimeter tumor compressed the foramen of Monroe and resulted in the death of a 76 y/o male [FA12-199].
      3. solitary fibrous tumor (SFT): is CD34 stem cell marker positive; histology can be remindful of a Schwannoma or leiomyoma with A & B zones or crossing fasicles, respectively (can occur in any body cavity & even the orbit [L07-9025].
      4. cavernoma: cavernous hemangioma (cavernous malformation).
    • malignant: one should avail oneself of the features of the gross pathology (imaging) & temporal profile of clinical features of the case; pathologist must press to get enough specimen for a full/accurate DX.
      1. metastatic lesions: choriocarcinomatous lesion [L07-10652] & pt. found to have a 520 gram testicular mass (nonseminomatous [L07-10864]).
      2. cystic:
        • cystic remnant of astrocytoma
      3. solid:
        1. meningeal: [L10-2073]
          1. menigioma.
          2. meningeal hemangiopericytoma [L10-12937?].
        2. glial:
          • astrocytoma (astroglioma): nuclei tend to have angulated, irregular chromatin and nuclear shape irregularities.
            • uncertain biological potential:
              • pilocytic astrocytomas
              • subependymal giant-cell astrocytomas
              • necrotizing glial neoplasm: so much necrosis (sometimes with suppuration and macrophages & uncertain glial cytology so that not sure of benign vs malignant [L08-12261]) as to be nondiagnostic by biopsy...a sort of default, possibly-false-negative category due to inadvertant under-sampling.
            • low grade (I/II): reactive and low grade can both have no mitoses & low ki67 on biopsy (as with reactive) but malignant tends to have staggered rather than smooth gradations of nuclear size variations among neighbor astrocytic cells and at least a small percentage with mildly hyperchromatic nuclei.
            • WHO grade II astrocytoma - Diffuse astrocytoma
              1. Fibrillary astrocytomas
              2. Protoplasmic astrocytoma
              3. Gemistocytic astrocytoma
              4. Pleomorphic xanthoastrocytoma
              5. choroid glioma
            • anaplastic astrocytoma (grade II of III or III of IV; WHO grade III). As approach "undifferentiatedness" can lose GFAP positivity.
              • usual; Ki67 of about 15% or higher & must find at least a mitosis or two [34 y/o injured head and 9mm ? tumor detected L09-1849].
              • small cell variant3 (can microcalcify [L08-10427...essentially a small cell GBM & acts like GBM ])
            • glioblastoma multiforme (GBM...WHO grade IV): mitoses, necrosis, & vascular proliferation. Primary (GBM from onset) vs. secondary (lesser-grade tumor evolves into GBM).
              • usual
              • giant cell GBM
              • gliosarcoma (Feigen tumor): pleomorphic spindled-cell malignancy (H&E remindful of MFH, spindled SCC, & melanoma), GFAP & vimentin pos. [L08-3199].
          • oligodendroglioma:
            • usual: often microcalcifications, chicken wire microvasculature, clear perinuclear haloes & perineuronal satellitosis. nuclei tend regular & round and fairly fine chromatin. Often marked by a 1p/19q chromosomal gene deletion (if deletion at both foci, predicts prolonged survival inj a pure "oligo".
            • anaplastic oligo: can look like small-cell ca./lymphoma at first, especially on FS [L08-12903; L10-8197, Ki67 20-30%].
          • mixed:
            • oligoastrocytoma: may look "oligo" but nuclei astrocytic [L08-9488] & neg. for the gene deletion.
        • Primary intracalvarial carcinoma:
        • Primary CNS lymphoma: [NGY11-1006/FNA12-570].
        • Primary intracalvarial sarcoma:


  1. Rosai J, Ackerman's Surgical Pathology, 9th Ed.
  2. specialists at our tumor board.
  3. Burger PC, et. al., "Small Cell Astrocytoma:...", Cancer 101(10):2318-2326, 15 Nov. 2004.

(posted  8 April, 2003; latest addition 10 September 2012)

© Copyright 1999 - 2006, all rights reserved, Pathology Associates Of Lexington, P.A.