PMC6222076_01
Nodular cystic lesion in the right posterolateral region of the anus.
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It was covered by a normal epidermis, with no ulcerations or signs of bleeding (Fig. 1).
(A, B) Magnetic resonance imaging of the pelvis with a single cystic, nodular image.
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The examination also showed that the lesion measured 2.5 x 1.7 x 2.2 cm, was not invading the sphincter muscle and rectal wall, and did not involve the coccyx or regional lymph node (Fig. 2A, B).
Nodular cystic excision.
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She was administered spinal anesthesia in the lithotomy position to excise the nodule; 1 cm circumferential safety margins were preserved (Fig. 3).
(A, B) Histology demonstrating squamous lesion with trichilemmal keratinization and largely comprised squamous cells with abrupt keratinization and containing hyaline areas.
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Histopathological examination of the excised specimen revealed a squamous lesion with trichilemmal keratinization and largely comprised squamous cells with abrupt keratinization and containing hyaline areas (Fig. 4A, B).
(A, B) Ki-67 demonstrated low mitotic index and CD34 expression, to differentiate the PTC from squamous cell carcinoma, also confirmed the diagnosis of trichilemmal cysts.
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CD34 expression, to differentiate the PTC from squamous cell carcinoma, also confirmed the diagnosis (Fig. 5A, B).