Article Figures & Data
Figures
- Fig 1.
Initial CT and 1.5T MR imaging. Axial CT (A) image shows a sharply delineated mass within the left temporal lobe with dense intralesional calcifications, with blooming signal on the corresponding SWI (B) (curved arrows in A and B). Heterogeneous signal was noted within the mass on both FLAIR (C) and T2WI (D) (curved arrows on C and D). Some peripheral areas appeared cystic (straight arrows, C and D). No substantial surrounding vasogenic edema was observed. A mild associated mass effect was observed, including partial effacement of the left lateral ventricle. Faint T1-hyperintense signal was noted in the central components of the tumor (straight arrows, E), while a greater extent of the mass demonstrated mild enhancement (straight arrows, F). A few tiny foci of mildly restricted diffusion were observed centrally (curved arrow, G), which corresponded with low-intensity signal on ADC images (not shown), though these may have been artifactual because no high-grade features were seen on pathology. Some of the solid-appearing components demonstrated elevated relative CBV (curved arrow, H).
- Fig 2.
7T MR imaging demonstrates internal characteristics of the mass on T2WI. From left to right (A–C), heterogeneous solid material is seen centrally (long straight arrows), while cystic components are located peripherally (short straight arrows). Fluid within the cysts is heterogeneous, but typically hypointense to CSF. A mild associated mass effect is seen, including partial effacement of the left lateral ventricle (curved arrows).
- Fig 3.
Presurgical mapping with fMRI and DTI performed on a 7T MR imaging scanner. Language fMRI (A–D) was accomplished using 5 different tasks: silent word generation (red), sentence completion (yellow), rhyming (cyan), reading comprehension (green), and semantic decision (magenta). In this left-handed patient, these tasks collectively demonstrated strong right-hemispheric lateralization of all 6 commonly identified language-activation sites, including the presupplementary motor area (Pre-SMA), language-related dorsolateral prefrontal cortex (DLPFC), Geschwind area (GA), Broca area (BA), Wernicke area (WA), and visual word form area (VWA).
- Fig 4.
Hematoxylin-eosin-stained photomicrographs show a prominent population of oligodendroglial cells with round-to-ovoid nuclei (arrow, A, scaled from 100×) as well as abundant calcifications, which appear as purple spherules of amorphous material (B, scaled from 100×). Immunohistochemical staining demonstrates uniformly positive nuclear OLIG2 expression (C, scaled from 100×), strong cytoplasmic expression of BRAF V600E (D, scaled from 200×), and widespread membranous expression of CD34 (E, scaled from 200×).
- Fig 5.
An artist’s illustration of a prototypical PLNTY. The tumors are typically located in the temporal lobe, well-circumscribed, and made up of mixed solid tissue, central calcifications (dashed arrow), and peripherally located cysts (curved arrow). Mass effect, if present, is usually minimal (short straight arrows). Reprinted with permission of the Mayo Foundation for Medical Education and Research. All rights reserved.
Tables
Comparison of clinical, imaging, and histopathologic characteristics of PLNTYs and oligodendrogliomas
PLNTY Oligodendroglioma Age at diagnosis (yr) 16–18 40–60 Most common location Temporal lobe Frontal lobe Tumoral border Well-circumscribed Poorly defined Calcification Heavily calcified, central location of calcifications Less prominent; calcifications are classically gyriform Intralesional signal Heterogeneous Heterogeneous Enhancement Minority of tumors, typically mild Minority of tumors, typically mild (described as dotlike) Intratumoral cysts ∼90% ∼50%
