Answer for BIR CoW 18 Oct 2020
Diffuse Astrocytoma –IDH Mutant Left Frontal
Findings
Well defined fairly large lesion with gradient blooming foci and minimal perilesional edma noted in left frontal parasagittal region involving the genu of corpus callosum in left . The lesion appears predominantly hyperintense in T2W1 and relatively hypointense in FLAIR with peripheral hyperintense rim reflective of T2 FLAIR –MISMATCH SIGN . Arterial spin labelled images show increased relative cerebral blood flow . On contrast administration, lesion shows heterogenous enhancement with few non enhancing areas Diffusion Tensor Imaging with Tractography shows partial disruption of the left corticospinal tract (in Blue colour). Functional MRI revealed the lesion is within 2 cms of the Primary Motor Cortex
Discussion
Features were consistent with Diffuse Astrocytoma –IDH Mutant Status The T2-FLAIR mismatch sign is an MRI appearance considered highly specific for Diffuse or Anaplastic Astrocytoma (IDH-mutant, 1p/19q-non-codeleted molecular status) as opposed to other lower grade gliomas. On T2WI, the tumor has homogeneously high signal intensity. On T2-FLAIR, the majority of the tumor has relatively hypointense signal, with the exception of a rim of hyperintensity. Age under 40 years at first diagnosis, a tumor size larger than 6 cm and T2-FLAIR mismatch were considered highly specific for IDH mutant astrocytoma. However , Recent articles reveals that the T2-FLAIR mismatch sign is not specific for diffuse astrocytoma, IDH-mutant & 1p19q non-codeleted and can be seen in cases of Dysembryoblastic Neuroepithelial Tumor as well
References:
1.T2-FLAIR mismatch sign in dysembryoplasticneuroepithelial tumor Shumpei Onishi Vishwa Jeet AmatyaManish KolakshyapatiKazuhiko SugiyamaKaoru Kurisu Fumiyuki Yamasaki Published:March 02, 2020DOI:https://doi.org/10.1016/j.ejrad.2020.1
2.Radiographic assessment of contrast enhancement and T2/FLAIR mismatch sign in lower grade gliomas: correlation with molecular groups Neurooncol 2019 Jan;141(2):327-335 Juratli TA, Tummala SS, Riedl A, Daubne et al
Findings
Well defined fairly large lesion with gradient blooming foci and minimal perilesional edma noted in left frontal parasagittal region involving the genu of corpus callosum in left . The lesion appears predominantly hyperintense in T2W1 and relatively hypointense in FLAIR with peripheral hyperintense rim reflective of T2 FLAIR –MISMATCH SIGN . Arterial spin labelled images show increased relative cerebral blood flow . On contrast administration, lesion shows heterogenous enhancement with few non enhancing areas Diffusion Tensor Imaging with Tractography shows partial disruption of the left corticospinal tract (in Blue colour). Functional MRI revealed the lesion is within 2 cms of the Primary Motor Cortex
Discussion
Features were consistent with Diffuse Astrocytoma –IDH Mutant Status The T2-FLAIR mismatch sign is an MRI appearance considered highly specific for Diffuse or Anaplastic Astrocytoma (IDH-mutant, 1p/19q-non-codeleted molecular status) as opposed to other lower grade gliomas. On T2WI, the tumor has homogeneously high signal intensity. On T2-FLAIR, the majority of the tumor has relatively hypointense signal, with the exception of a rim of hyperintensity. Age under 40 years at first diagnosis, a tumor size larger than 6 cm and T2-FLAIR mismatch were considered highly specific for IDH mutant astrocytoma. However , Recent articles reveals that the T2-FLAIR mismatch sign is not specific for diffuse astrocytoma, IDH-mutant & 1p19q non-codeleted and can be seen in cases of Dysembryoblastic Neuroepithelial Tumor as well
References:
1.T2-FLAIR mismatch sign in dysembryoplasticneuroepithelial tumor Shumpei Onishi Vishwa Jeet AmatyaManish KolakshyapatiKazuhiko SugiyamaKaoru Kurisu Fumiyuki Yamasaki Published:March 02, 2020DOI:https://doi.org/10.1016/j.ejrad.2020.1
2.Radiographic assessment of contrast enhancement and T2/FLAIR mismatch sign in lower grade gliomas: correlation with molecular groups Neurooncol 2019 Jan;141(2):327-335 Juratli TA, Tummala SS, Riedl A, Daubne et al
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!