Orofacial Epidermoid Cysts: A Case Series

ABSTRACT

Epidermoid cysts can occur anywhere in the body but are uncommon in the orofacial region, with a 7% incidence in the head and neck and 1.6% in the oral cavity. We diagnosed two cases in the left cheek and successfully operated on them through an intraoral approach.

Summary.

• Epidermoid cysts are rare in the orofacial region, comprising less than 0.01% of all oral cavity cysts.

• Here, we report two cases of epidermoid cysts on the left cheek of a 61‐year‐old and a 39‐year‐old male, both successfully treated via an intraoral approach without complications.

1. Introduction

Cysts are commonly found in the oral and maxillofacial regions and are broadly classified into odontogenic and non‐odontogenic cysts [1, 2]. Odontogenic cysts exhibit characteristic odontogenic markers, histological similarities with odontogenic tissue, and specific anatomical locations [2]. Non‐odontogenic cysts, such as epidermoid cysts, arise from non‐odontogenic structures in the oral and maxillofacial region [2].

Epidermoid cysts can develop anywhere in the body but are rare in the orofacial region [3, 4, 5]. Their incidence is 7% in the head and neck region and 1.6% in the oral cavity, accounting for less than 0.1% of all oral cavity cysts [4, 5, 6, 7]. In the oral cavity, these cysts commonly develop on the floor of the mouth, tongue, lips, palate, jaw, and cheek [3, 5, 7]. Known by various names such as epidermal inclusion cyst, epidermal cyst, follicular cyst infundibular type, epidermoid inclusion cyst, and keratin cyst, they are slow‐growing benign lesions appearing as firm nodules in the subcutaneous tissue [8, 9, 10]. These cysts are predominantly found in males and are derived from the epidermis, with histology showing a lining of stratified squamous epithelial tissue filled with keratinous semi‐solid materials [4, 5, 8, 9, 10].

Here, we report two cases of epidermoid cysts in the left cheek that were successfully treated using an intraoral approach.

2. Case Presentation

2.1. Case 1

2.1.1. Case History/Examination

A 61‐year‐old male patient presented to our Oral and Maxillofacial Surgery outpatient department with a chief complaint of swelling in the left cheek for 2 years. The swelling was slowly increasing in size and was not associated with pain, trismus, weight loss, or regional lymphadenopathy. The patient had no significant medical, family, or allergic history.

On clinical examination, a solitary, localized, oval‐shaped, firm, non‐tender, and mobile mass, measuring 3 × 2 × 2 cm, was observed on the left cheek. The mass was not fixed to the underlying oral mucosa. It extended anteriorly to 1 cm posterior to the left oral commissure, posteriorly to 1 cm anterior to the tragus, superiorly to 1 cm below the infraorbital rim, and inferiorly to 1 cm above the lower border of the mandible (Figure 1). Aspiration of the lesion with an 18‐gauge needle was unsuccessful due to thick, semisolid cystic content.

FIGURE 1.

Extraoral photograph showing swelling on the left cheek.

2.1.2. Differential Diagnosis, Investigations and Treatment

The differential diagnosis for the lesion included lipoma, fibroma, pleomorphic adenoma, dermoid cyst, and epidermoid cyst. Ultrasonography (USG) and Fine Needle Aspiration Cytology (FNAC) were performed.

Ultrasonography revealed a heteroechoic lesion measuring 1.7 × 2.7 × 2.8 cm in the subcutaneous plane overlying the buccinator muscle. The lesion exhibited no evidence of vascularity or calcification. FNAC of the left cheek confirmed the presence of an epidermoid cyst.

Surgical excision of the lesion under general anesthesia was planned using a transoral approach to avoid skin scarring. Routine blood investigations were conducted, and the results were within normal limits. The detailed procedure was explained to the patient, and written informed consent was obtained. The patient was prepared for surgery with the usual preoperative measures. He was positioned supine. Nasotracheal intubation was performed, parts were prepared, and a throat pack was placed.

Lignocaine 2% with adrenaline (1:80,000) was infiltrated at the incision site in the buccal mucosa to reduce bleeding. A 3 cm intraoral horizontal incision was made at the occlusal plane level with a number 15 BP blade over the buccal mucosa at the most prominent part of the swelling. Blunt dissection was performed through the buccinator muscle to explore the cystic lesion. During further dissection, a cheesy, grayish‐white, keratinous material was extruded from the lesion. The complete cystic lining was excised and sent for histopathological examination (Figure 2). The surgical site was irrigated with 0.9% NaCl, hemostasis was achieved, and primary closure was performed. Analgesics and antibiotics were prescribed postoperatively, and daily dressing was done for 7 days. After 7 days, the sutures were removed, and healing was satisfactory without any complications.

FIGURE 2.

A. Intraoral incision through the buccal mucosa revealing a cystic lesion. B. Specimen showing intracystic contents and cystic lining.

2.1.3. Outcome and Follow‐Up

2.1.3.1. Histopathological Examination (HPE)

Microscopic examination revealed a cystic cavity lined by ortho‐keratinized stratified squamous epithelium with a prominent granular cell layer. The cystic lumen contained abundant lamellated keratin. The epithelial‐connective tissue interface was flat, and the underlying capsule exhibited dense bundles of collagen fibers with focal areas of hyalinization. The HPE findings were indicative of an epidermoid cyst (Figure 3).

FIGURE 3.

(A) 4X magnification, H&E stain showing a cystic cavity filled with keratin and lined by stratified squamous epithelium. (B) 40X magnification, high‐power view showing a cystic cavity lined by keratinized stratified squamous epithelium with a prominent granular cell layer.

A 1‐year follow‐up showed no signs of recurrence, and the patient is doing well.

2.2. Case 2

2.2.1. Case History/Examination

A 39‐year‐old male patient presented with a chief complaint of swelling in the left cheek for 2 years. The swelling was slowly increasing in size, was not associated with any other symptoms, and had no relevant history.

On clinical examination, a solitary, localized, oval‐shaped, firm, non‐tender, and mobile mass measuring 3 × 2 × 1 cm was observed on the left cheek. It extended anteriorly to 5 mm posterior to the left oral commissure, posteriorly to 2 cm anterior to the angle of the mandible, superiorly to the line connecting the left oral commissure to the earlobe, and inferiorly to 5 mm above the lower border of the mandible (Figure 4A). Aspiration of the lesion with an 18‐gauge needle was negative.

FIGURE 4.

(A) Extraoral photograph showing swelling on the left cheek. (B) Intraoral incision through the buccal mucosa revealing the cystic lesion.

2.2.2. Investigations and Treatment

Ultrasonography demonstrated a well‐defined cystic lesion in the subcutaneous plane overlying the buccinator muscle of the left cheek, lateral to the oral commissure. The lesion measured 2.8 × 1.9 × 1.3 cm. Color Doppler imaging revealed no vascularity, while low‐level internal echoes were observed, consistent with the characteristics of an epidermoid cyst. Fine‐needle aspiration cytology (FNAC) of the left cheek confirmed the presence of an epidermoid cyst.

Surgical excision of the lesion under general anesthesia was planned using a transoral approach. A 2.5 cm intraoral horizontal incision was made 5 mm below the occlusal plane level with a number 15 BP blade over the buccal mucosa at the most prominent part of the swelling. Blunt dissection was performed through the buccinator muscle to explore the cystic lesion (Figure 4B). During further dissection, a cheesy, grayish‐white, keratinous material was extruded from the lesion. The complete cystic lining was excised and sent for histopathological examination (Figure 5A). Primary closure was performed.

FIGURE 5.

(A) Specimen showing intracystic contents and cystic lining. (B) 10X magnification, showing the cystic cavity lined by stratified squamous epithelium with a prominent granular cell layer. The cystic cavity contains flecks of keratin.

2.2.3. Outcome and Follow‐Up

2.2.3.1. Histopathological Examination

The microscopic section reveals a cyst wall lined by keratinized stratified squamous epithelium with a prominent granular cell layer. The cystic space contains numerous keratin flakes, and the subepithelium shows fibro‐collagenous tissue. There was no inflammatory infiltrate, sebaceous glands, hair follicles, dysplasia, or malignancy observed. These histopathological findings confirm the diagnosis of an epidermoid cyst (Figure 5B).

A 1‐year follow‐up showed no signs of recurrence, and the patient's condition remains favorable.

3. Discussion

Epidermoid cysts are benign, firm, slow‐growing nodules usually asymptomatic and present in the subcutaneous tissue [3, 4, 5]. Although they can occur anywhere in the body, their occurrence in the orofacial region is rare [3, 4, 5]. They may occasionally occur in the temporomandibular joint (TMJ) region when skin tissue is utilized as an interpositional material during the surgical management of TMJ ankylosis [11]. These cysts specifically form in areas where embryonic elements fuse [7] and can be either congenital or acquired, often resulting from traumatic skin damage [9].

Epidermoid cysts may present as isolated lesions in otherwise healthy individuals or may be associated with syndromic conditions such as Gorlin syndrome, Gardner syndrome, and hereditary familial polyposis [7, 8, 9]. Comprehensive genetic studies are necessary to rule out underlying syndromic associations. In the present cases, the lesions occurred in healthy individuals without any syndromic association.

Clinically, the primary differential diagnoses of an epidermoid cyst in the cheek include:

Dermoid Cyst: Similar to epidermoid cysts but contains adnexal structures such as sebaceous glands and hair follicles.

Sebaceous Cyst (Pilar Cyst): Originates from sebaceous glands, often containing oily or cheesy material with a visible punctum.

Lipoma: A soft, mobile, and non‐tender lesion composed of adipose tissue, typically lacking a central punctum.

Abscess: Characterized by localized redness, tenderness, and fluctuance due to infection.

Lymphadenopathy: Firm and mobile, often associated with systemic infections or malignancies.

Benign or Malignant Salivary Gland Tumors: Arise from minor salivary glands and may present as firm and fixed masses.

Neurofibroma: A soft, non‐tender lesion often associated with neurofibromatosis.

Branchial Cleft Cyst: A congenital lesion commonly located along the anterior border of the sternocleidomastoid, with possible extension into the cheek.

Fibroma: A firm, slow‐growing lesion often linked to chronic irritation.

Vascular Malformations (Hemangioma/Lymphangioma): Hemangiomas present as compressible lesions with a bluish discoloration and blanching on compression [5, 8, 9].

A thorough clinical examination is essential for differentiating an epidermoid cyst from other similar lesions.

Palpation: Epidermoid cysts are firm, round, mobile, and non‐tender unless infected. Lipomas are soft and doughy, whereas fibromas are firmer. Lymph nodes are usually firm and may be tender in cases of infection.

Presence of a Punctum: Epidermoid cysts often exhibit a visible central punctum, indicative of an obstructed duct. Sebaceous cysts may also have a punctum, whereas lipomas and fibromas do not.

Fluctuation Test: Epidermoid cysts may exhibit mild fluctuation but are typically firmer than abscesses. Abscesses present with significant tenderness, warmth, and redness.

Transillumination: Epidermoid cysts do not transilluminate, whereas dermoid cysts and vascular malformations may.

Compression and Color Change: Hemangiomas blanch upon compression, unlike epidermoid cysts.

Systemic Symptoms: Lymphadenopathy may be associated with fever or infection. Malignant lesions are often firm, fixed, and may ulcerate over time.

Aspiration and Cytology: Aspiration of an epidermoid cyst yields keratinous debris, while sebaceous cysts yield oily material.

Imaging and Diagnostic Confirmation: Ultrasonography is Useful for differentiating solid and cystic lesions.

MRI/CT Scan: Recommended for deeper lesions or suspected invasion into adjacent structures.

Fine‐Needle Aspiration Cytology (FNAC) and Core Biopsy: Essential for histopathological confirmation.

A comprehensive evaluation integrating patient history, palpation, punctum identification, fluctuation testing, transillumination, and aspiration can effectively rule out other differential diagnoses. In the current cases, USG and FNAC were utilized to confirm the diagnosis of an epidermoid cyst.

According to a study by Kim CS et al., epidermoid cysts are most common in patients in their 40s and 50s, followed by those in their 20s, 30s, and 60s [9]. Studies by Ham and Kim found that most affected patients were in their 20s, while Heo and Oh noted that most cases occurred in patients in their 30s and 40s [9]. Kumar et al. reported that the majority of affected patients were in their second and third decades of life [5]. In the present cases, the patients were 61 and 39 years old, aligning with the literature.

The most common location for epidermoid cysts varies widely, with some studies identifying the trunk and others the face as the most frequent sites [9]. In the head and neck region, common sites include the lateral eyebrow and the floor of the mouth, corresponding to areas of embryonic fusion [5, 7]. In the present cases, the lesions were located on the left cheek.

Several mechanisms have been proposed for the development of epidermoid cysts, including the proliferation of ectodermal remnants during embryogenesis, traumatic implantation of epithelial tissue, and obstruction of the pilosebaceous unit [5, 12, 13].

The size of epidermoid cysts in the literature ranges from 1 to 5 cm [5, 7]. In the present cases, the lesions measured 1.7 × 2.7 × 2.8 cm and 2.8 × 1.9 × 1.3 cm, consistent with the literature.

Histopathological examination typically reveals a cystic cavity lined by a four‐ to eight‐cell layer of ortho‐keratinized stratified squamous epithelium, with a prominent granular cell layer and a cystic cavity containing laminated keratin material [5]. The cystic wall comprises dense bundles of collagen with fibroblasts and blood vessels, findings that were also present in the present cases [5].

Surgical excision is the treatment of choice for epidermoid cysts, which can be approached either transorally or extraorally, depending on the lesion's location [14]. In the present cases, the lesions were excised using an intraoral approach. Although an extraoral approach would have provided easier access for excision, it would have resulted in an unesthetic surgical scar on the face. The intraoral approach was chosen for this procedure to avoid any facial scarring.

Recurrence is rare, accounting for less than 3% of cases due to the thick fibrous capsules that facilitate enucleation [5, 7]. In the present cases, no sign of recurrence was observed in the 1‐year follow‐up.

4. Conclusion

The incidence of epidermoid cysts in the orofacial region is rare. The characteristics of the lesions observed in this study align with existing literature. Surgical excision is the preferred treatment for such lesions, with recurrence being uncommon.

4.1. Patient's Perspective

The patient expressed a high level of satisfaction with the successful treatment, which was completed without any complications.

Author Contributions

Manoj Adhikari: conceptualization, data curation, formal analysis, funding acquisition, investigation, methodology, project administration, resources, software, supervision, validation, visualization, writing – original draft, writing – review and editing. Kanistika Jha: conceptualization, data curation, formal analysis, funding acquisition, investigation, methodology, project administration, resources, supervision, validation, visualization, writing – original draft, writing – review and editing. Puja Thapa: conceptualization, data curation, formal analysis, methodology, resources, software, supervision, validation, visualization, writing – original draft, writing – review and editing. Sarita K.C.: conceptualization, data curation, investigation, methodology, project administration, resources, software, supervision, validation, visualization, writing – original draft, writing – review and editing. Padam Raj Neupane: conceptualization, formal analysis, investigation, methodology, resources, supervision, validation, visualization, writing – original draft, writing – review and editing. Pratibha Poudel: conceptualization, formal analysis, resources, supervision, validation, visualization, writing – original draft, writing – review and editing.

Ethics Statement

It is our routine standard surgical procedure so ethical clearance was not required from the institution's ethics committee, Nepalese Army Institute of Health Sciences.

Consent

Written informed consent was obtained from both the patients to publish this case report in accordance with the journal's patient consent policy.

Conflicts of Interest

The authors declare no conflicts of interest.

Data Availability Statement

The authors have nothing to report.