glioblastoma with signet-ring cells
Primary central nervous system tumors with signet-ring morphology are exceedingly rare.
Synopsis
highly anaplastic tumor
tumor cells exhibiting signet-ring
classic round cytoplasmic inclusions
eccentrically positioned nuclei
Immunochemistry
glial fibrillary acidic protein +
S100 +
negative for cytokeratins
Ultrastructure
intermediate filaments
FISH
intact 1p/19q
Differential diagnosis
The presence of signet-ring cells in the central nervous system should immediately raise the suspicion of metastatic carcinoma, particularly from the upper gastrointestinal tract.
Reference
Glioblastoma with signet-ring morphology: a case report and review of the literature. Martin SE, Bonnin JM, Hall DC, Hattab EM. Hum Pathol. 2009 Nov 30. PMID: #19954819#