Fig. 3

Histopathological phenotypes of NMDAR-E associated teratoma presenting histological features of gliomas. a-c Case #4. Hematoxylin-phloxine-saffron (HPS) staining (a) of the solid nervous tissue containing monotonous cells surrounded by perinuclear cytoplasmic halos (“fried-egg” oligodendrocytes-like cells) mixed with a vascular network consisting of short geometrically-arranged capillary segments, consistent with the histopathological observations of an oligodendroglioma. Some tumor cells showed positivity for Olig2 expression (b) but low Ki-67 proliferation index (c). d-f Case #5. HPS staining (d) of the neuroglial tissue showing increased cellular density, clusters of ganglion cells and aligned oligodendrocytes-like cells, consistent with the histological features of a ganglioglioma. Some tumor cells were found to be positive for Olig2 expression (e) and the Ki-67 proliferation index was increased in the perivascular area (f). g-i Case #6. HPS staining (g) of the nervous tissue with highly elevated cellular density and pleiomorphic or poorly differentiated cells, consistent with the histopathological aspect of a malignant glioma. Some tumor cells show positivity for Olig2 expression (h) and elevated Ki-67 proliferation index (i). Scale bar: 100 μm