Endogenous chemical exchange saturation transfer (CEST) MR imaging for the diagnosis and therapy response assessment of brain tumors: A systematic review
Purpose: To generate a narrative synthesis of published data on the use of endogenous
chemical exchange saturation transfer (CEST) MR imaging in brain tumors.
Materials and Methods: A systematic database search (PubMed, Ovid Embase, Cochrane
Library) was used to collate eligible studies. Two researchers independently screened
publications according to predefined exclusion and inclusion criteria, followed by
comprehensive data extraction. All included studies were subjected to a bias risk assessment
using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool.
Results: The electronic database search identified 430 studies, of which 36 studies fulfilled
the inclusion criteria. The final selection of included studies was categorized into 5 groups as
follows: grading gliomas, 19 studies (areas under the curve (AUC) 0.500-1.000); predicting
molecular subtypes of gliomas, 5 studies (AUC 0.610-0.920); distinction of different brain
tumor types, 7 studies (AUC 0.707-0.905); therapy response assessment, 3 studies (AUC not
given) and differentiating recurrence from treatment-related changes, 5 studies (AUC 0.880-
0.980). A high bias risk was observed in a substantial proportion of studies.
Conclusion: Endogenous CEST imaging offers valuable, potentially unique information in
brain tumors, but its diagnostic accuracy remains incompletely known. Further research is
required to assess the method’s role in support of molecular genetic diagnosis, to investigate
its use in the post treatment phase, and to compare techniques with a view to standardization