PMC8769460_01
Preoperative neuroradiological examination. (A) Plain CT showing an iso-to-hypo-dense tumor in the right temporal lobe including a small calcified area. Preoperative MRI showing the tumor in the right temporal lobe. (B and C) The tumor appears as a heterogeneous hyperintense lesion on diffusion-weighted imaging (DWI) (B) and T2-weighted imaging (T2) (C). (D) T1-weighted imaging (T1) showing a hypointense lesion with a hyperintense spotty area. (E) Partial enhancement of the capsule seen on T1 after gadolinium administration (T1Gd(+)).
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F1
Plain CT scan of the brain (Fig. 1A) revealed an iso-to-hypo-dense mass lesion in the right temporal lobe with a diameter of 3.0 x 2.8 x 3.0 cm including a small calcified area. T2-weighted imaging (T2, Fig. 1C). T1-weighted imaging (T1, Fig. 1D) showed a hypointense lesion with a hyperintense spotty area. In addition, partial enhancement of the capsule was seen in T1 after injection of gadolinium contrast (Fig. 1E).
Operative view during right temporal craniotomy. The lumen is filled with keratinized material (arrowhead) including hair (arrow). The capsule (double arrow) is thick, hard, and elastic.
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F2
Gross total resection of the tumor was achieved through a right temporal craniotomy (Fig. 2).
Hematoxylin-eosin staining (A and B: bar: 100 mum, C: bar: 20 mum). (A) The cyst wall is lined with stratified squamous epithelium. The outer layer of the wall is accompanied by connective tissue with vascular aggregates (arrowheads) and sebaceous glands (arrows). The cyst lumen is filled with keratinized material (double arrow). (B) Inflammation is confirmed on parts of the tumor wall with lymphocyte infiltration (arrow), aggregation of small vessels (arrow heads), and cholesterol crystal deposition (white arrowhead). (C) Deposition of hemosiderin is seen (white arrows).
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F3
The cyst wall was composed of squamous epithelium with connective tissue containing small vascular aggregates (Fig. 3A and 3B) and sebaceous glands (Fig. 3A). The cyst lumen was filled with keratin flakes (Fig. 3A). Inflammation was confirmed in the parts of the tumor wall with lymphocyte infiltration, deposition of cholesterol crystals (Fig. 3B), and deposition of hemosiderin (Fig. 3C).
Postoperative MRI showing total resection of the tumor. (A) DWI. (B) T1. (C) T1Gd(+).
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F4
Postoperative MRI (Fig. 4A-C) confirmed complete resection of the tumor.