Absence of enhancement in a lesion does not preclude primary central nervous system T-cell lymphoma: A case report

Table 2 The pathologic report

Immunohistochemical	P53: Positive
	CD68: Positive in the microglia
	Glial Fibrillary Acidic Protein: Positive in the reactive astrocytes
	Myeloperoxidase: Negative
	K27M: Negative
	Vimentin: Focal positive in the lymphocytes and reactive astrocytes
	CD56: Nonspecifically positive
	Phospho-Histone H3: 23/10 HPFs
	LFB: Positive in the myelin sheath (no loss of myelin sheath)
	Isocitrate Dehydrogenase 1: Negative (no mutation)
	EZHIP: Negative
	Olig2: Focal positive
	TMHH3 (Lys27): Positive (no mutation)
	CD3: Some CD3-positive T-cells infiltration
	CD20: A few positive cells in a perivascular area
	IBA-1: Positive in the microglia
	Ki-67: Positive in 40.0%
	CD8: A few positive cells
Electronic microscopy	Ultrathin sections show sheets of round to oval-shaped neoplastic lymphoid cells. The nuclei of tumor cells are round to oval with heterochromatin and prominent nucleoli. The cytoplasm is scanty and contains eccentrically located a few mitochondria and electron-dense granules
Diagnosis	Brain, putamen, left, stereotactic biopsy: Scattered proliferative T-cell infiltration, consistent with T-cell lymphoma

CD: Cluster of differentiation; LFB: Luxol fast blue; EZHIP: Enhancer of Zest homologs inhibitory protein; Olig2: Oligodendrocyte transcription factor 2; TMHH3 (lys27): Trimethylation at lysine 27 of histone H3; IBA-1: Ionized calcium-binding adaptor molecule 1; Ki-67: Antigen Kiel-67.