case_images: PMC11301574_01
case_images: Representative non-contrast CT brain images in axial (A) and coronal (B) views. Both depict a predominantly acute intraparenchymal hematoma (6.8 x 6.4 x 5.6 cm) in the right frontoparietal region, with associated cerebral edema and mass effect. There is intraventricular extension of hemorrhage with early hydrocephalus. Subfalcine and mild right uncal herniation is seen. (C) Representative T1-weighted post-contrast MRI brain images in axial view. There is an irregular, ill-defined lesion with a heterogeneous signal, intermixed with blood products centered in the right frontoparietal region. The previous leftward midline shift has improved. Of note, there are foci of nodular enhancement in the periphery of the lesion that likely represent residual tumor. (D) Representative screenshot of relevant tractography (main corticospinal fibers in blue) in relation to the tumor (yellow-gold) from Modus Plan (Synaptive Medical, Toronto, Canada). This is a neurosurgical planning software that uses preoperative diffusion MRI data to segment out the patient's white matter tracts.
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case_images: PMC11301574_01_fped-12-1378608-g001.jpg
case_images: F1
case_images: There was no radiological evidence of spinal metastases (Figure 1). Mitotic figures were present at 1 mitotic figure/mm2, and the Ki-67 index was up to 5%.
case_images: (A) Hematoxylin and eosin slide of tumor and it comprises of epithelioid to spindle cells, several of which feature large pleomorphic nuclei. Occasional cells show xanthomatous change. There is also intervening hemorrhage between the pleomorphic and xanthomatous cells. (40x) (B) Hematoxylin and eosin slide showing blood vessels with perivascular hyalinization in some areas. (10x) (C) This is a slide that shows the presence of eosinophilic bodies amongst the tumor cells. (40x) (D) Hematoxylin and eosin slide showing a well-demarcated border between the tumour and adjacent brain, without obvious infiltration. (x10). Next, immunohistochemical staining shows areas of that confirms GFAP (E), CD34 (F), S100 (G), and NeuN (H) positivity, respectively. (I) This is a slide that shows staining for reticulin deposited in several areas. (J) There is notable cytoplasmic positivity for ALK on IHC. However, follow-up molecular investigations via NGS techniques are negative for ALK (as mentioned in the main text). (All slides depicted here are 20x magnification, unless otherwise stated).
case_images: fped-12-1378608-g002.jpg
case_images: PMC11301574_01_fped-12-1378608-g002.jpg
case_images: F2
case_images: Mitotic figures were present at 1 mitotic figure/mm2, and the Ki-67 index was up to 5%. Other illustrative details of the findings are described in Figures 2 and 3.
case_images: (A) Immunohistochemical stain for pan-TRK shows dot-like cytoplasmic positivity. (20x). This finding was followed up with the Archer FusionPlex Pan-Solid Tumour V2 (Invitae, San Francisco, CA, USA) for the patient's tumor whereby the results of the ETV6::NTRK3 fusion were found. The diagram also includes a screenshot analysis of the anchored multiplex PCR result. Here, an ETV6::NTRK3 fusion transcript with a percentage of unique reads (66%) spanning the breakpoint and supporting the event is identified. (B) Representative FISH image result of patient's tumor tissue. This shows the ratio of 9p21/CEP9 is 0.35, with 56% of tumor nuclei enumerated. There is no 9p21 signal, and 18% show only one copy of 9p21. Overall, these findings concur with the tumor being positive for CDKN2A deletion.
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case_images: PMC11301574_01_fped-12-1378608-g003.jpg
case_images: F3
case_images: Other illustrative details of the findings are described in Figures 2 and 3. This investigation demonstrated the presence of an ETV6::NTRK gene fusion (Figure 3A). The tumor was then further interrogated by the Ampliseq Childhood Cancer Panel (Illumina, San Diego, CA, USA), another NGS-based targeted gene panel, which also confirmed the presence of the ETV6::NTRK fusion.