Pleomorphic adenoma of the palate is a rare benign tumor of the minor salivary glands. The palate is the most frequent site, followed by the lips and the soft palate. Its intraoral location may lead to swallowing, respiratory, and phonatory disorders when significantly enlarged [1]. The objective of this study was to report two clinical cases of pleomorphic adenoma of the palate managed in our ENT-HNS department in Parakou in 2025.

Case1:

This was a 24-year-old student with no significant medical history, admitted with a 2-month history of palatal swelling. Progressive enlargement of the swelling was associated with intermittent dysphagia. Physical examination revealed a palatal mass measuring approximately 5 cm in greatest dimension, non-tender, firm in consistency, and covered with normal-appearing mucosa (Figure 1). Examination of the lymph node regions was unremarkable. Facial computed tomography revealed a 45 mm mixed-density tumor of the palate, lateralized to the left, with no associated bone destruction (Figure 2). Fine-needle aspiration cytology (FNAC) was not performed.

Figure 1. Intraoral view showing a left palatal mass.

Figure 2. CT scan of the facial skeleton; (a) coronal section: blue arrow indicating a palatal tumor; (b) sagittal section: brown arrow indicating a palatal tumor; (c) axial section: yellow arrow indicating a palatal tumor.

Surgical management consisted of excision under general anesthesia (Figure 3). Following an incision of the palatal mucosa approximately 1 cm from the tumor margin, meticulous dissection was carried down to the periosteum. The palatal mucosa was preserved to cover the surgical defect, which was closed with a single-layer suture. Postoperatively, the patient received nasogastric tube feeding to promote healing of the intraoral wound because of the palatal mucosal suture. Histopathological examination revealed a solid-cystic lesion that appeared encapsulated macroscopically. Histologically, it consisted of a tumor proliferation with dual epithelial and myoepithelial components. These elements were embedded in a myxoid stroma, with no signs of malignancy. The surgical margins were free of tumor. The findings were therefore consistent with a benign lesion of pleomorphic adenoma type (Figure 4). The postoperative course was uneventful, with satisfactory healing of the surgical wound and removal of the nasogastric tube on postoperative day 10. The outcome was favorable, with no signs of recurrence at the 13-month follow-up (Figure 5).

Figure 3. Excision of a palatal mass with preservation of the palatal mucosa. (a) removal of the palatal tumor; (b) blue arrow indicating preserved healthy overlying palatal mucosa.

Figure 4. (a) surgical specimen measuring approximately 5 cm in greatest dimension; (b) H & E staining, ×400: tumor composed of epithelial and myoepithelial components.

Figure 5. Postoperative course; (a) postoperative status on day 1; (b) healing of the palatal mucosa at 1 month; (c) healing at 12 months.

Case2:

This was a 25-year-old farmer with no significant medical history, admitted with a 6-year history of palatal swelling. The swelling gradually increased in size, causing intermittent dysphagia to solids.

Physical examination revealed a right-sided palatal mass extending to the soft palate, measuring approximately 6 cm in greatest dimension and 5 cm in its smallest dimension, non-tender, firm in consistency, and covered with normal-appearing mucosa (Figure 6). There was no bleeding upon contact. Examination of the lymph node regions was unremarkable. Facial computed tomography revealed an expansile lesion of the right hemi-palate measuring 8 cm in its greatest dimension, with contrast enhancement. There was no bone involvement (Figure 7).

Figure 6. Right palatal mass evident on mouth opening.

Figure 7. Facial computed tomography. (a) axial section showing a right palatal tumor without bone erosion (blue arrow); (b) sagittal section showing the palatal lesion (blue arrow).

After completion of the preoperative assessment, excision under general anesthesia with preservation of the palatal mucosa was performed (Figure 8). Postoperatively, the patient received nasogastric feeding to promote healing of the sutured intraoral wound. Histopathological examination concluded that the lesion was benign and consistent with pleomorphic adenoma of the minor salivary glands of the palate, with 80% myoepithelial component and 20% epithelial component (Figure 9). The postoperative course was uneventful, with healing of the surgical wound and removal of the nasogastric tube on postoperative day 14. The outcome was favorable with a follow-up of 12 months without tumor recurrence (Figure 10).

Figure 8. Gross surgical specimen measuring 6 cm in greatest dimension.

Figure 9.Histopathology, case 2: H & E staining, ×400, showing 80% myoepithelial and 20% epithelial components, consistent with pleomorphic adenoma.

Figure 10. Postoperative course; (a) immediate postoperative appearance on day 1; (b) healing at 3 months postoperatively.

Strict adherence to ethical standards was maintained throughout the preparation of the medical records, including respect for anonymity, privacy, patient information, and informed consent for the use of data in scientific research. Compliance with principles of integrity, professional independence, absence of conflicts of interest, and assessment of risks to patient health was also ensured.

Pleomorphic adenoma accounts for approximately 50% of all salivary gland tumors, both major and minor [2]. It represents the most frequent histological type, accounting for 70.6% to 100% of benign minor salivary gland tumors, with a predilection for the palate [3]. Wu et al. in Taiwan reported 74 cases of pleomorphic adenoma out of 78 cases (94.8%) of benign tumors of the minor salivary glands [4]. Over a one-year period, two cases were managed at our department in Parakou. This tumor is rarely encountered in our setting. Pleomorphic adenoma affects individuals of all ages, with a predilection for young adults between the third and fifth decades according to the literature [4][5]. However, Hamid et al. found that pleomorphic adenoma was more frequently observed in individuals aged 20 to 40 years [6]. In our context, patients were in their third decade of life. In Japan, the study by Katsutoshi et al. demonstrated a female predominance, with females accounting for 63.6% of cases [5]. The literature reports that pleomorphic adenoma of the minor salivary glands more frequently affects women than men [3][5][7]. However, our study included only two male patients. Given the small number of cases over a single year, we cannot conclude that men are predominantly affected in our region. Clinically, pleomorphic adenoma of the palate presents as an asymptomatic submucosal palatal mass that progressively increases in size. It is generally firm and non-ulcerated [8]. In the absence of early management, progressive growth leads to increased tumor volume, which may compromise vital functions such as feeding, breathing, and phonation [1]. In our study, the pleomorphic adenoma was left-sided in one case and right-sided in the second case. No correlation was observed between sex and tumor laterality. The mucosa overlying the tumor was normal in both patients, and no palatal destruction was noted. Pleomorphic adenoma usually arises laterally on the palate. It should be differentiated from torus palatinus, a benign midline bony protuberance.

In the series by Hamama J., CT scanning revealed a palatal tumor with homogeneous tissue density, well-defined and regular margins, and moderate contrast enhancement, associated with thinning of the overlying bone [9]. Some authors, such as Yoshiyuki Iida et al. in Japan, combined CT with magnetic resonance imaging (MRI), reporting a well-circumscribed oval lesion [10]. The MRI appearance depends on the cellular and myxoid composition of the tumor. This tumor is often lobulated, well circumscribed, hypointense on T1-weighted images and hyperintense on T2-weighted images, with homogeneous enhancement after contrast administration [11]. We performed facial CT scans in both cases because magnetic resonance imaging is not available at our Parakou center. The lesion was well circumscribed, and the absence of palatal bone erosion is an important feature of pleomorphic adenoma that helps distinguish it from a malignant tumor. After contrast administration, heterogeneous enhancement was observed. Bone erosion may be observed in 21.7% of cases. In his study, Wu et al. reported 47 classic pleomorphic adenomas and 27 cellular pleomorphic adenomas. No myxoid-type pleomorphic adenoma was observed. Among the 74 palatal pleomorphic adenomas, 12 were completely encapsulated, 40 partially encapsulated, and 22 were non-encapsulated [4]. Juan Araya et al. described a proliferation of epithelial and myoepithelial cells, some with a plasmacytoid appearance, forming ductal structures containing eosinophilic secretory material with a mesenchymal myxoid component [12]. Both of our cases exhibited myoepithelial and epithelial components, with predominance of myoepithelial cells. Pleomorphic adenoma (PA) is characterized by a mixture of epithelial and myoepithelial cells embedded in a variable stromal background. Immunohistochemistry may be useful to confirm the diagnosis.

Surgical management involved complete excision under general anesthesia while sparing the palatal mucosa. In large lesions, tracheostomy ensures adequate airway control [1]. Wu et al. reported only one case of local recurrence of the lesion in a patient after a follow-up period ranging from 5.8 to 21.3 years [4]. Pleomorphic adenoma has a variable recurrence rate ranging from 2% to 45% [13]. Malignant transformation is possible in 6.2% of pleomorphic adenomas of the salivary glands [14]. In Parakou, no recurrence was observed after one year of follow-up although the follow-up period was relatively short. A longer follow-up period of at least 10 years would be necessary to confidently confirm a favorable outcome without recurrence.

Pleomorphic adenoma of the palate is a benign tumor of the oral cavity. It may progressively enlarge and compromise swallowing function. Management is surgical and relies on complete excision to reduce the risk of recurrence.

Bouraïma, F.A., Mahada, U: conception, surgery, writing, editing, review.

Avakoudjo, F.: conception, writing, editing.

Oteyami, B., Agbokponto, A., Affokpon, B.: surgery.

Beheton, R., Flatin, M.-C.: review.