Abstract

Objectives Oxygen 6-methylguanine-DNA methyltransferase (MGMT) promoter methylation is a significant prognostic biomarker
in astrocytomas, especially for temozolomide (TMZ) chemotherapy. This study aimed to preoperatively predictMGMTmethylation
status based on magnetic resonance imaging (MRI) radiomics and validate its value for evaluation of TMZ chemotherapy effect.
Methods We retrospectively reviewed a cohort of 105 patients with grade II-IV astrocytomas. Radiomic features were extracted
from the tumour and peritumoral oedema habitats on contrast-enhanced T1-weighted images, T2-weighted fluid-attenuated inversion
recovery images and apparent diffusion coefficient (ADC) maps. The following radiomics analysis was structured in three
phases: feature reduction, signature construction and discrimination statistics. A fusion radiomics signature was finally developed
using logistic regression modelling. Predictive performance was compared between the radiomics signature, previously reported
clinical factors and ADC parameters. Validation was additionally performed on a time-independent cohort (n = 31). The prognostic
value of the signature on overall survival for TMZ chemotherapy was explored using Kaplan Meier estimation.
Results The fusion radiomics signature exhibited supreme power for predicting MGMT promoter methylation, with area under
the curve values of 0.925 in the training cohort and 0.902 in the validation cohort. Performance of the radiomics signature
surpassed that of clinical factors and ADC parameters. Moreover, the radiomics approach successfully divided patients into highrisk
and low-risk groups for overall survival after TMZ chemotherapy (p = 0.03).
Conclusions The proposed radiomics signature accurately predictedMGMT promoter methylation in patients with astrocytomas, and
achieved survival stratification for TMZ chemotherapy, thus providing a preoperative basis for individualised treatment planning.