Grading of IDH-mutant astrocytoma using diffusion, susceptibility and perfusion-weighted imaging

Abstract

Abstract Background The accurate grading of IDH-mutant astrocytoma is essential to make therapeutic strategies and assess the prognosis of patients. The purpose of this study was to investigate the usefulness of DWI, SWI and DSC-PWI in grading IDH-mutant astrocytoma. Methods One hundred and seven patients with IDH-mutant astrocytoma who underwent DWI, SWI and DSC-PWI were retrospectively reviewed. Minimum apparent diffusion coefficient (ADC min ), intratumoral susceptibility signal intensity(ITSS) and maximum relative cerebral blood volume (rCBV max ) values were assessed. ADC min , ITSS and rCBV max values were compared between grade 2 vs. grade 3, grade 3 vs. grade 4 and grade 2 + 3 vs. grade 4 tumors. Logistic regression, tenfold cross-validation,and receiver operating characteristic (ROC) curve analyses were used to assess their diagnostic performances. Results Grade 4 IDH-mutant astrocytomas showed significantly lower ADC min and higher rCBV max as compared to grade 3 tumors (adjusted P < 0.001). IDH-mutant grade 3 astrocytomas showed significantly lower ITSS levels as compared with grade 4 tumors (adjusted P < 0.001). ITSS levels between IDH-mutant grade 2 and grade 3 astrocytomas were significantly different (adjusted P = 0.002). Combined the ADC min , ITSS and rCBV max resulted in the highest AUC for differentiation grade 2 and grade 3 tumors from grade 4 tumors. Conclusion ADC min, rCBV max and ITSS can be used for grading the IDH-mutant astrocytomas. The combination of ADC min, ITSS and rCBV max could improve the diagnostic performance in grading of IDH-mutant astrocytoma.