Case report
A 56-year-old man in a good heath was referred to the Oral Medecine and Oral Surgery department at the university clinic of dental medecine, Monastir, Tunisia, with the chief complaint of a painless swelling in the left buccal mucosa for about 5 years. The patient had neither known drug allergies, or history of surgery and/or trauma related to the lesion area.
Extraoral examination revealed the presence of a solitary swelling in the left cheek covered by normal looking skin in color and texture, as well. The swelling was nontender and freely mobile to the skin, on palpation (figure 1). No submental nor submandibular lymphadenopathy were detected.
Intraoral examination showed a poor oral hygien and a nodule in the left buccal mucosa covered by a healthy mucosa (figure 2). The mass was soft and non mobile on palpation.
Due to these clinical findings, the initial diagnosis was benign tumor of either the oral mucosa (including vascular lesions) or the salivary gland.
An ultrasonography was required. It revealed a well defined walled hyperechoic heterogenous lesion measuring 34×31×21 mm with posterior ultrasound reinforcement in the left buccal mucosa (figure 3). Vascular lesions were excluded on Colour Doppler analysis. At this stage, the diagnosis of epidermoid cyst of the left buccal mucosa was evoked.
Under local anesthesia and with intraoral access, the lesion was completely removed.
An horizontal incision in the buccal mucosa was conducted exposing a cyst immediately underlying the mucosa.
The enucleation was carefully done. Accidentally, when a partial rupture of the wall was happened, a yellow liquid was observed (figure 4).
The surgical wound was closed using a 4.0 silk suture, and the specimen was stored in 10% formol for further anatomopathological study (figure 5).
The postoperative period was uneventful and healing was good.
Histopathological examination of the surgical specimen revealed a cystic cavity. The cyst wall is composed of keratinized stratified squamous epithelium with keratin debris and no skin appendages (figure 6). This wall contains a foreign-body giant-cell reaction (figure 7).
These finding were suggestive of epidermoid cyst of the buccal mucosa.