Patients
This study was approved by the Ethical Institution of our hospital.
Medical records from patients aged over 3 years with high-risk MB
between January 1st, 2010 and December
31st, 2018, were reviewed. High-risk MB was defined as
residual disease >1.5 cm2, diffuse
anaplasia histology and metastatic spread of disease (M0,1,2,3)
according to the Chang’s classification[6]. Patients receiving
intrathecal MTX were classified into MTX group, while those without
intrathecal MTX into control group. Patients in WNT subgroup were
excluded due to the good previous treatment response.
The following data were extracted from each patient, including age,
gender, histological subtype, tumor stage, risk group, molecular
subgroup, chemotherapy regimen and dosage, details of MTX intracranial
injection, clinical manifestation of leukoencephalopathy, treatment
regimen of leukoencephalopathy, and patient outcomes (including the
cause of death). Data collection from clinical records of patients was
approved by the Institutional Review Boards. All data were anonymous,
and informed consent was waived due to the retrospective observational
nature of this study. Additionally, written informed consents were
obtained from the parents or legal guardians of patients before the
initiation of chemotherapy.