Intrathecal methotrexate in combination with systemic chemotherapy in glioblastoma patients with leptomeningeal dissemination: A retrospective analysis

Table 1 Clinical characteristics of the patients at the time of glioblastoma diagnosis

Variable	N (%)
Patient	26 (100)
Age at GBM diagnosis: median (range)	43 (18-61)
Sex
Female	10 (38.5)
Male	16 (61.5)
Location
Infratentorial (cerebellum)	2 (7.7)
Supratentorial	24 (92.3)
Extent of resection of GBM at diagnosis
Gross total	7 (26.9)
Non-gross total	19 (73.1)
Communicating with the ventricle at time of GBM diagnosisa
Yes	18 (69.2)
No	8 (30.8)
Concurrent radiation + TMZ after GBM diagnosis
Yes	26 (100)
No	0 (0)
Adjuvant TMZ cycles for GBM: Median (range)	7 (1-20)
< 7	15 (57.7)
≥ 7	11 (42.3)
Molecular pathology, positive testb
MGMT methylation	5 (19.2)
IDH1 mutation	1 (3.8)
TERT C228T mutation	8 (30.8)

^aThe tumor was within 1 cm of the ventricular system or the ventricular system was open during the operation.

^bPositive test for immunohistochemistry or NextGen sequencing.

GBM: Glioblastoma; TMZ: Temozolomide; IDH: Isocitrate dehydrogenase; LMD: Leptomeningeal dissemination; MGMT: O6-methylguanine-DNA methyltransferase; TERT: Telomerase reverse transcriptase.