Table 1.

Epidemiological summary and immunohistochemical result of studied IDH-mutant oligodendrogliomas and astrocytomas.

Oligodendroglioma	CNS WHO grade 2 (n = 28, 37.8%)	CNS WHO grade 3 (n = 46, 62.2%)		Total (n = 74)
Median age (years) (range)	44.5 (19 ~ 66)	45.5 (23 ~ 68)		45 (19 ~ 68)
Male to female ratio	1:1	1:1.1		1:1.1
Frontal lobe	60.7% (17/28)	54.3% (25/46)		56.8% (42/74)
Multiple lobes	21.4% (6/28)	26.1% (12/46)		24.3% (18/74)
Temporal lobe	7.1% (2/28)	8.7% (4/46)		8.1% (6/74)
Insula	7.1% (2/28)	2.2% (1/46)		4.1% (3/74)
Parietal lobe	3.6% (1/28)	4.3% (2/46)		4.1% (3/74)
Cingulate	0	4.3% (2/46)		2.7% (2/74)
Primary: recur	3:1	1.1:1		1.6:1
Median Ki-67 (range)	6.3% (2.2 ~ 7.5)	22.55% (13.4 ~ 60.4)
Median mitotic rate (range)	2/10 HPF (0 ~ 7)	8/10 HPF (1 ~ 54)

Astrocytoma	CNS WHO grade 2 (n = 16, 16.8%)	CNS WHO grade 3 (n = 43, 45.3%)	CNS WHO grade 4 (n = 36, 37.9%)	Total (n = 95)
Median age (years) (range)	48 (20 ~ 69)	40 (21 ~ 68)	40 (14 ~ 75)	41 (14 ~ 75)
Male to female ratio	2.2:1	1.2:1	2:1	1.6:1
Frontal lobe	68.8% (11/16)	39.5% (17/43)	47.2% (17/36)	47.4% (45/95)
Multiple lobes	18.8% (3/16)	20.9% (9/43)	36.1% (13/36)	26.3% (25/95)
Temporal lobe	0	20.9% (9/43)	2.8% (1/36)	10.5% (10/95)
Parietal lobe	6.3% (1/16)	7.0% (3/43)	8.3% (3/36)	7.4% (7/95)
Insula	6.3% (1/16)	7.0% (3/43)	0	4.2% (4/95)
Occipital lobe	0	0	2.8% (1/36)	1.1% (1/95)
Paracentral lobule	0	2.3% (1/43)	0	1.1% (1/95)
Lateral ventricle	0	2.3% (1/43)	0	1.1% (1/95)
Cerebellum	0	0	2.8% (1/36)	1.1% (1/95)
Median Ki-67 index (range)	2.1% (0.2 ~ 4.8)	7.4% (2.0 ~ 57.2)	28.6% (5.6 ~ 90.2)	8.8% (1.2 ~ 90.2)
Median mitotic rate (range)	1/10 HPF (0 ~ 2)	6/10 HPF (3 ~ 77)	12/10 HPF (4 ~ 108)	41/10 HPF (0 ~ 108)