PMC7256210_01
(A) Panoramic radiograph showing a dislocated third molar in the right maxillary sinus (arrow). (B) Sagittal CT scan shows OKC in the right maxillary sinus involving the third molar which has extended into the pterygoid process of the sphenoid bone near the skull base. (C) Axial CT scan. (D) Coronal CT scan.
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Panoramic radiography showed an ill-defined and radiopaque lesion in the right maxillary sinus involving the third molar that had been displaced to the roof of the sinus (Fig. 1A). Computed tomography (CT) scan revealed an irregularly dense cystic lesion that entirely occupied the right maxillary sinus extending to the right pterygoid process of the sphenoid bone near the skull base (Fig. 1B to 1D).
(A) Intraoperative image after removal of the anterior wall of the maxillary sinus showing OKC involvement with a third molar (arrow). (B) Postoperative image showing a bone window to access into the pterygoid process (arrow). (C) Surgical specimen of OKC with the third molar. A larger piece of the lesion was in the maxillary sinus and a smaller one in the pterygoid process.
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We performed enucleation of the cyst and removal of the displaced third molar using the Caldwell-Luc procedure which in this case extended the surgical approach to the right pterygoid process of the sphenoid bone via the pterygomaxillary junction (Fig. 2A to 2C).
H & E stain and immunohistochemistry for bcl-2 and cytokeratin-10 of the surgical specimen. (A) H & E stain reveals the specimen to be OKC (original magnification x200). (B) Immunohistochmical staining shows bcl-2 expression in the basal layer (original magnification x200). (C) No staining is observed for cytokeratin-10 (original magnification x200).
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The boundary between the epithelium and connective tissue was flat and a palisade arrangement was observed in the epithelial basal cells (Fig. 3A). Immunohistochemistry for bcl-2 showed limited expression of the basal layer of OKC lining whereas no expression was found for cytokeratin-10 staining (Fig. 3B and 3C).
CT scans show recurrent OKC in the posterior wall of the right maxillary sinus (arrows). (A) Axial scan. (B) Sagittal scan. (C) Coronal scan.
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However, we found a recurrent lesion in the posterior wall of the maxillary sinus on CT scan 20 months after the surgery (Fig. 4A to 4C).
(A) Intraoperative image showing the recurrent lesion in the posterior wall of the right maxillary sinus (arrow). (B) Postoperative image after removal. (C) Surgical specimen of recurrent OKC.
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The patient subsequently underwent a secondary cystectomy (Fig. 5A to 5C) and histopathological examination confirmed the specimen to be OKC.
Follow-up CT scans show no recurrent lesion after a secondary cystectomy. (A) Axial scan. (B) Sagittal scan. (C) Coronal scan.
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No evidence of recurrence has been observed over the second postoperative period of 20 months (Fig. 6A to 6C).