Premium
A case of congenital supratentorial tumor: Atypical teratoid/rhabdoid tumor or primitive neuroectodermal tumor?
Author(s) -
Nishihira Yasushi,
Tan ChunFeng,
Hirato Junko,
Yoshimura Junichi,
Nishiyama Kenichi,
Takahashi Hideaki,
Fujii Yukihiko,
Takahashi Hitoshi
Publication year - 2007
Publication title -
neuropathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.701
H-Index - 61
eISSN - 1440-1789
pISSN - 0919-6544
DOI - 10.1111/j.1440-1789.2007.00809.x
Subject(s) - atypical teratoid rhabdoid tumor , vimentin , pathology , glial fibrillary acidic protein , immunostaining , primitive neuroectodermal tumor , immunohistochemistry , biology , cd99 , neuroectodermal tumor , medicine
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT.