PMC4258724_01
(a) Noncontrast CT scan of brain in axial plane reveal mass lesion in the left parieto- occipital region with dense calcification. (b) Noncontrast CT scan of brain in a more superior axial plane showing the tumor extending up to the trigone of left lateral ventricle with perilesional edema
SNI-5-506-g001.jpg
PMC4258724_01_SNI-5-506-g001.jpg
F1
Computed tomography (CT) scan of brain showed a tumor of size 3.5 x 3.2 x 2.9 cm in the left parieto-occipital region extending up to the trigone [Figure 1].
(A) Photomicrograph showing lobules of tumor with osseous and cartilaginous metaplasia. (Stain, hematoxylin and eosin; original magnification, x200.) (B) (a-f) Photomicrograph showing tumor cells (a,b) arranged in the form of cords and trabeculae embedded in a hyalinized matrix, (c) focal physaliphorous like cells, (d,e) osseous and cartilaginous metaplasia, and (f) tumor infiltrating surrounding brain. (Stain, hematoxylin and eosin; original magnification, x400.) (C) (a-f) Photomicrograph of the immunohistochemical panel showing tumor cell positivity for (a) pancytokeratin, (b) vimentin, (c) focal S-100 and (d) EMA. (e) Ki67 nuclear expression with a labeling index of 2% and (f) negative expression for GFAP. (Stain, diaminobenzidine x400)
SNI-5-506-g002.jpg
PMC4258724_01_SNI-5-506-g002.jpg
F2
The intervening stroma was fibrous and showed chondromyxoid areas with foci of osseous metaplasia [Figure 2a and b]. Thyroid transcription factor (TTF), Cytokeratin 7 and 20, P63, and CD99 [Figure 2c]. The
Chromosomal analysis of cultured peripheral blood lymphocytes. GTC - banded karyotypic analysis revealed no numerical or structural chromosome abnormalities and indicated a normal male karyotype
SNI-5-506-g003.jpg
PMC4258724_01_SNI-5-506-g003.jpg
F3
Ki 67 labeling index was 2%. The microscopic findings along with the immunohistochemistry favored a diagnosis of parachordoma. Karyotype analysis of chromosomes did not reveal any abnormality [Figure 3].
Contrast enhanced T1W MRI scan in axial plane (a), coronal plane (b), sagittal plane (c) at one year follow up showing completely resected tumor replaced by gliotic changes
SNI-5-506-g004.jpg
PMC4258724_01_SNI-5-506-g004.jpg
F4
Follow-up contrast enhanced MRI scan of brain at one year follow-up, showed no recurrence of the tumor with adjacent gliotic changes [Figure 4].
18F-fluorodeoxyglucose (FDG)PET/CT scan done at one year follow-up showing no evidence of intracranial or extracranial lesions. Fig 5a showing maximum intensity projection in coronal plane. (b) showing lateral view of FDG-PET scan
SNI-5-506-g005.jpg
PMC4258724_01_SNI-5-506-g005.jpg
F5
A whole-body positron emission tomography (PET) CT scan at one year follow-up did not show any other lesion [Figure 5].