TY - JOUR
T1 - The T2-FLAIR mismatch sign as an imaging marker for non-enhancing IDH-mutant, 1p/19q-intact lower-grade glioma
T2 - a validation study
AU - Broen, Martinus P. G.
AU - Smits, Marion
AU - Wijnenga, Maarten M. J.
AU - Dubbink, Hendrikus J.
AU - Anten, Monique H. M. E.
AU - Schijns, Olaf E. M. G.
AU - Beckervordersandforth, Jan
AU - Postma, Alida A.
AU - van den Bent, Martin J.
PY - 2018/10
Y1 - 2018/10
N2 - Background. The purpose of this study was to assess the reproducibility of the previously described T2-fluid attenuated inversion recovery (FLAIR) mismatch sign as a specific imaging marker in non-enhancing isocitrate dehydrogenase (IDH) mutant, 1p/19q non-codeleted lower-grade glioma (LGG), encompassing both diffuse and anaplastic astrocytoma.Methods. MR scans (n = 154) from 3 separate databases with genotyped LGG were evaluated by 2 independent reviewers to assess (i) presence/absence of "T2-FLAIR mismatch" sign and (ii) presence/absence of homogeneous signal on T2-weighted images. Interrater agreement with Cohen's kappa (.) was calculated, as well as diagnostic test performance of the T2-FLAIR mismatch sign to identify IDH-mutant astrocytoma.Results. There was substantial interrater agreement for the T2-FLAIR mismatch sign [kappa = 0.75 (0.64-0.87)], but only fair agreement for T2 homogeneity [kappa = 0.38 (0.25-0.52)]. The T2-FLAIR mismatch sign was present in 38 cases (25%) and had a positive predictive value of 100%, negative predictive value of 68%, a sensitivity of 51%, and a specificity of 100%.Conclusions. With a robust interrater agreement, our study confirms that among non-enhancing LGG the T2-FLAIR mismatch sign represents a highly specific imaging marker for IDH-mutant astrocytoma. This non-invasive marker may enable a more informed patient counsel and can aid in the treatment decision processes in a significant proportion of patients presenting with non-enhancing, LGG-like lesions.
AB - Background. The purpose of this study was to assess the reproducibility of the previously described T2-fluid attenuated inversion recovery (FLAIR) mismatch sign as a specific imaging marker in non-enhancing isocitrate dehydrogenase (IDH) mutant, 1p/19q non-codeleted lower-grade glioma (LGG), encompassing both diffuse and anaplastic astrocytoma.Methods. MR scans (n = 154) from 3 separate databases with genotyped LGG were evaluated by 2 independent reviewers to assess (i) presence/absence of "T2-FLAIR mismatch" sign and (ii) presence/absence of homogeneous signal on T2-weighted images. Interrater agreement with Cohen's kappa (.) was calculated, as well as diagnostic test performance of the T2-FLAIR mismatch sign to identify IDH-mutant astrocytoma.Results. There was substantial interrater agreement for the T2-FLAIR mismatch sign [kappa = 0.75 (0.64-0.87)], but only fair agreement for T2 homogeneity [kappa = 0.38 (0.25-0.52)]. The T2-FLAIR mismatch sign was present in 38 cases (25%) and had a positive predictive value of 100%, negative predictive value of 68%, a sensitivity of 51%, and a specificity of 100%.Conclusions. With a robust interrater agreement, our study confirms that among non-enhancing LGG the T2-FLAIR mismatch sign represents a highly specific imaging marker for IDH-mutant astrocytoma. This non-invasive marker may enable a more informed patient counsel and can aid in the treatment decision processes in a significant proportion of patients presenting with non-enhancing, LGG-like lesions.
KW - IDH-mutant astrocytoma
KW - imaging marker
KW - lower grade glioma
KW - T2-FLAIR
KW - 1P/19Q CO-DELETION
KW - MOLECULAR CLASSIFICATION
KW - CLINICAL-PERSPECTIVE
KW - RESECTION
KW - MUTATION
KW - STRATIFICATION
KW - IDENTIFICATION
KW - SURVIVAL
KW - LOSSES
KW - TUMORS
U2 - 10.1093/neuonc/noy048
DO - 10.1093/neuonc/noy048
M3 - Article
C2 - 29590424
VL - 20
SP - 1393
EP - 1399
JO - Neuro-oncology
JF - Neuro-oncology
SN - 1522-8517
IS - 10
ER -