[Apparent Diffusion Coefficient Histogram Analysis:Differentiation of Genetic Subtypes of Diffuse Lower-grade...

Area of Science:

• Neuroimaging
• Oncology
• Radiology
• Biostatistics

Background:

• Diffuse lower-grade gliomas (WHO grade II/III) exhibit diverse genetic subtypes.
• Accurate genetic subtyping is crucial for prognostication and treatment planning.
• Non-invasive methods to differentiate these subtypes are highly desirable.

Purpose of the Study:

• To evaluate the effectiveness of apparent diffusion coefficient (ADC) histogram analysis in differentiating genetic subtypes of diffuse lower-grade gliomas.
• To assess the diagnostic performance of various ADC histogram parameters in distinguishing between IDH-wildtype, IDH-mutant 1p19q-intact, and IDH-mutant 1p19q-codeleted gliomas.

Main Methods:

• Retrospective analysis of 55 patients with WHO grade II/III diffuse lower-grade gliomas.
• Preoperative MRI including diffusion-weighted imaging (DWI) was performed.
• Whole-lesion ADC histogram parameters were calculated and compared between genetic subtypes using statistical tests (t-test, Mann-Whitney U) and ROC analysis.

Main Results:

• Significant differences in ADC histogram parameters were observed between IDH-wildtype and IDH-mutant gliomas.
• ADC parameters like inhomogeneity and standard deviation showed high diagnostic performance in differentiating IDH-mutant from IDH-wildtype gliomas (AUC=0.811).
• The 'mode' parameter demonstrated good performance in distinguishing IDH-mutant 1p19q-intact from IDH-mutant 1p19q-codeleted gliomas (AUC=0.744).

Conclusions:

• ADC histogram analysis is a valuable tool for non-invasively differentiating genetic subtypes of lower-grade gliomas.
• This technique can aid in the diagnostic workup and classification of gliomas based on their genetic profiles.
• Further validation in larger cohorts is warranted to fully integrate ADC histogram analysis into clinical practice.