Most PAs harbor Rosenthal fibers within their compact or fibrillary areas.
Eosinophilic granular bodies may also be present but are often fewer than Rosenthal fibers (Figure 2a-2d).
PMAs lack Rosenthal fibers and a biphasic pattern and exceptionally demonstrate rare eosinophilic granular bodies.
Both models exhibit disease-associated protein deposits called Rosenthal fibers
There was a well-defined fibrillary glial proliferation, with occasional fragments of Rosenthal fibers similar to that seen in a pilocytic astrocytoma (Figure 2(a)).
(a) The tumor has a fibrillary glial background with occasional Rosenthal fibers (arrows).
(1) Alexander disease is a rare leukodystrophy characterized by astrocytic cytoplasmic inclusions called Rosenthal fibers
. Most cases are attributed to a mutation of the GFAP (glial fibrillary acidic protein) gene, which causes abnormal function or gain of function in the GFAP.
No eosinophilic granular bodies, Rosenthal fibers
, or Herring bodies were identified within the tumors.
In contrast to PA, Rosenthal fibers
, eosinophilic granular bodies and calcifications tend to be absent or uncommon in PMA, though Gottfired et al., described a PMA case with Rosenthal fibers
, and microcalcifications (5).
No Verocay bodies, thick-walled blood vessels, Rosenthal fibers, granular bodies, calcifications, or psammoma bodies were present.
In contrast with pilocytic astrocytomas, pituicytomas lack Rosenthal fibers, granular bodies, and biphasic morphologic structure.