Answer for BIR CoW 16 Feb 2025
OLIGODENDROGLIOMA
Findings
Evidence of Relatively well defined cortical based hypodense lesion in Right parietal lobe measures approximately ,3.2x 2.5x 3 cm in size with multiple internal gyriform calcifications noted.
Discussion
Oligodendrogliomas(ODGs) are well – differentiated , slow –growing but diffusely infiltrating hemispheric tumors that most likely arise from oligodendrocytes or immature glial stem cells. Most ODGs arise at gray- white matter junction. The vast majority are supratentorial. The most common site is the frontal lobe, followed by parietal , temporal and occipital lobe. MICROSCOPIC FEATURES: ODGs are highly cellular lesions. Uniform round or oval hyperchromatic nuclei surrounded by perinuclear halo, gives classic FRIED EGG APPEARANCE . Delicate angulated capillaries (“ chicken wire” vascularity)are often present, but florid microvascular proliferation is absent. GENETICS:ODGs characterised by IDH Mutation (either IDH1 or IDH2) and 1p and 19qdeletion. Canonical ODGS – IDH Mutated, 1p19qdeletion without necrosis, florid microvascular proliferation or marked mitotic activity, are designated as WHO Grade II neoplasms. ODGs arise between ages of 35-55 yrs. CT Findings: ODGs are peripheral and cortical based hypodense lesion. Focal Gyral expansion with thinning and remodelling of the overlying calvaria is common. Coarse nodular or clumped calcification is seen Enhancement varies from none to moderate . MRI: ODGs often appear hypointense in T1, heterogeneously hyperintense on T2/ FLAIR. Calcification is seen as blooming foci on T2* sequences. Moderate heterogenous enhancement seen. ODGs do not restrict on DWI. MRS: Moderate choline peak and decreased NAA peak with an elevated 2 hydroxyglutarate resonating at 2.25 ppm. MR Perfusion: Low grade ODGs are highly vascular and metabolically active , display high rCBV foci that reflect the prominent chicken wire vascularity characteristic of IDH –Mutated , 1p19q deleted ODGs.
Reference: Osborn brain –imaging, pathology & Anatomy
Findings
Evidence of Relatively well defined cortical based hypodense lesion in Right parietal lobe measures approximately ,3.2x 2.5x 3 cm in size with multiple internal gyriform calcifications noted.
Discussion
Oligodendrogliomas(ODGs) are well – differentiated , slow –growing but diffusely infiltrating hemispheric tumors that most likely arise from oligodendrocytes or immature glial stem cells. Most ODGs arise at gray- white matter junction. The vast majority are supratentorial. The most common site is the frontal lobe, followed by parietal , temporal and occipital lobe. MICROSCOPIC FEATURES: ODGs are highly cellular lesions. Uniform round or oval hyperchromatic nuclei surrounded by perinuclear halo, gives classic FRIED EGG APPEARANCE . Delicate angulated capillaries (“ chicken wire” vascularity)are often present, but florid microvascular proliferation is absent. GENETICS:ODGs characterised by IDH Mutation (either IDH1 or IDH2) and 1p and 19qdeletion. Canonical ODGS – IDH Mutated, 1p19qdeletion without necrosis, florid microvascular proliferation or marked mitotic activity, are designated as WHO Grade II neoplasms. ODGs arise between ages of 35-55 yrs. CT Findings: ODGs are peripheral and cortical based hypodense lesion. Focal Gyral expansion with thinning and remodelling of the overlying calvaria is common. Coarse nodular or clumped calcification is seen Enhancement varies from none to moderate . MRI: ODGs often appear hypointense in T1, heterogeneously hyperintense on T2/ FLAIR. Calcification is seen as blooming foci on T2* sequences. Moderate heterogenous enhancement seen. ODGs do not restrict on DWI. MRS: Moderate choline peak and decreased NAA peak with an elevated 2 hydroxyglutarate resonating at 2.25 ppm. MR Perfusion: Low grade ODGs are highly vascular and metabolically active , display high rCBV foci that reflect the prominent chicken wire vascularity characteristic of IDH –Mutated , 1p19q deleted ODGs.
Reference: Osborn brain –imaging, pathology & Anatomy
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
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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!