Second Surgery in Insular Low-Grade Gliomas

Table 1

Demographic, clinical, neuroradiological, and pathological data at first surgery.

Parameter	Value
Number of patients	53
Sex
Female	23 (43.40%)
Male	30 (56.60%)
Mean age (yrs)	38 (range 19–69)
Tumor side
Left	36 (67.92%)
Right	17 (32.08%)
Median preoperative T2 tumoral volume in cm^3 (range)	76.33 (range 5–174)
Median preoperative ΔVT2T1 value in cm^3 (range)	23.13 (range 1–112)
ΔVT2T1 category
<30 cm^3	37 (69.81%)
≥30 cm^3	16 (30.19%)
Intraoperative protocol
Awake surgery	41 (77.36%)
General anesthesia	12 (22.64%)
Cortical mapping
Speech arrest and motor function orbicularis oris	All 41 cases with lesion involving the dominant hemisphere
Slurred speech or dysarthria	26 (49%)
Anomia	26 (49%)
Subcortical mapping
Identification of corticospinal tract as posterior edge of resection	All cases
Identification of subcortical language pathways	Positive sites were detected in 24 cases (45.3%)
Neurophysiological data
Reversible reduction of MEPs amplitude	7 out of 10 patients, who developed postoperative transient motor deficit
Irreversible MEPs loss	In 1 patient who showed, after surgery, a permanent motor deficit
Median EOR in % (range)	82.98 (range 54–100)
EOR category
≥90%	22 (41.51%)
70–89%	23 (43.40%)
<70%	8 (15.09%)
Immediate postoperative clinical findings
No deficits	37 (69.81%)
Neurological deficits	15 (30.19%)
Motor deficits	9 (16.98%)
Speech disorders	6 (13.21%)
Clinical outcome 6 months after surgery
No deficits	52 (98.11%)
Neurological deficits	1 (1.89%)
Postoperative Engel Class 6 months after surgery
I	36 (67.92%)
II	4 (7.55%)
III	8 (15.10%)
IV	5 (9.43%)
Histological diagnosis
Fibrillary astrocytoma	31 (58.5%)
Oligodendroglioma	6 (11.3%)
Oligoastrocytoma	16 (30.2%)
Molecular profile
Mib1-Ki-67 expression	3.5% (range 1–5%)
1p/19q codeletion presence	13 (25%)
P53 expression	33 (62.26%)
IDH1 mutation	45 (85%)
MGMT promoter methylation	39 (73.58%)