Patient Data
Note: This case has been tagged as "legacy" as it no longer meets image preparation and/or other case publication guidelines.
Cystic pineal lesion with blood product in the dependent portion, and T1 hyperintense anterior compartment. No solid nodular enhancement.
Case Discussion
This patient went on to have a biopsy/drainage of the cyst.
Histology
Microscopic Description:
Sections show a single fragment of glial tissue lined by ependymal cells. The reactive changes include fibrillary astrocytes and frequent Rosenthal fibers. Some infiltration by macrophages and lymphocytes as identified by H & E stain and immunohistochemistry (HAM-56 and LCA respectively). Immunohistochemistry reveals strong positivity of the astrocytes for GFAP (glial fibrillary acidic protein). There are some cells showing nuclear positivity for MIB-1. Immunohistochemistry for phosphorylated neurofilaments reveals very rare linear axon-like structures. Iron stain shows that many of the above-mentioned macrophages contain hemosiderin granules.
Final Diagnosis:
Ependymal-lined glial tissue with fibrillary astrocytes, Rosenthal fibers, macrophages, and occasional lymphocytes
The histologic findings of the small biopsy are consistent with fibrillary gliosis of subependymal tissue adjacent to a lesion. However, given the anatomic location of the lesion, the differential diagnosis would also include, but would not be limited to, the glial component of a pineal cyst and a pilocytic astrocytoma. The small biopsy size precludes a definitive diagnosis in this regard.