|Year : 2015 | Volume
| Issue : 2 | Page : 317-319
Pleomorphic adenoma of the palate
Prathima Shetty1, Prashanth K Shenai1, Laxmikanth Chatra1, Prasanna Kumar Rao1, Rajesh Shetty2
1 Department of Oral Medicine and Radiology, Yenepoya Dental College, Yenepoya University, Mangalore, Karnataka, India
2 Department of Prosthodontics, Yenepoya Dental College, Yenepoya University, Mangalore, Karnataka, India
|Date of Web Publication||16-Dec-2015|
Department of Oral Medicine and Radiology, Yenepoya Dental College, Yenepoya University, University Road, Nithyanand Nagar Post, Deralakatte, Mangalore - 575 018, Karnataka
Source of Support: None, Conflict of Interest: None
Pleomorphic adenoma is a benign salivary gland tumor commonly affecting in the major salivary glands. Incidence of pleomorphic adenoma affecting minor salivary gland tumors has also been reported. Presenting a case report of a 48-year-old male diagnosed with pleomorphic adenoma arising from minor salivary gland.
Keywords: Minor salivary gland, palate, pleomorphic adenoma
|How to cite this article:|
Shetty P, Shenai PK, Chatra L, Rao PK, Shetty R. Pleomorphic adenoma of the palate. Arch Med Health Sci 2015;3:317-9
| Introduction|| |
Salivary gland tumors constitute <3% of all head and neck tumors.  Almost all salivary gland tumors occur in the major salivary glands, especially the parotid gland. Minor salivary gland tumors constitute <20% of all salivary gland neoplasms. Among all salivary gland tumors, pleomorphic adenoma is one of the commonly encountered lesions, occurring in approximately 60% of all salivary gland tumors. Among the major salivary gland tumors, Pleomorphic adenoma is associated with parotid gland (53-77%), submandibular gland (44-68%), and minor salivary glands (4-6%). Among minor salivary gland tumors, Palate is the most commonly affected site.  The other intraoral sites affected are lips, buccal mucosa, tongue, floor of the mouth, and retromolar triangle. 
| Case Report|| |
A 48-year-old male patient reported to the outpatient department of Oral Medicine and Radiology, with a chief complaint of swelling in the palate for the past 12 years. Initially, the swelling was smaller in size and was not associated with any type of pain or discomfort. He had consulted many physicians in the past for the same reason and was advised to go for biopsy and treatment that the patient declined. For the past 1-year, the swelling was growing and gained 5 cm × 5 cm dimension. It was associated with difficulty in eating and speech. His medical and family history was noncontributory. Patient had a habit of smoking eight beedis daily for the past 15 years.
A well-defined solitary swelling on the right side of the palate extending anteriorly to 1/3 rd of the hard palate, posteriorly extending into the soft palate, laterally from right maxillary canine to right maxillary third molar region and medially crossing the midline of the palate was observed. The dimension of the swelling was around 5 cm × 5 cm anteroposteriorly, and oval in shape. Overlying mucosa was smooth except one area where it was pointed. There was no discharge from the swelling, its border was distinct, and color was normal. Mucosa adjacent to the swelling appeared normal [Figure 1]. Swelling was firm in consistency, noncompressible, nonfluctuent, nonmobile and nontender. On Aspiration, it did not yield any content. Vitality test confirmed that all the teeth were vital.
Hence, based on the history given by the patient and the clinical examination carried out, a provisional diagnosis of pleomormic adenoma of the palate was made. The clinical differential diagnosis considered for the swelling were periapical cyst, periodontal cyst, mucoepidermoid carcinoma and adenoid cystic carcinoma.
Paranasal sinus view showed no sinus involvement, but soft tissue shadow was noticed [Figure 2].
Incisional biopsy was done, and the microscopic section showed proliferation of epithelial and myoepithelial cells arranged in duct-like structures with the presence of mucin, myxomatous hyalinized areas. Large percentage of tumor cells contains myoepithelial cells arranged in the angular pattern. Surface epithelium was stratified squamous with papillary areas. Capsule was seen covering the lesion [Figure 3]. With all these features, a final diagnosis of pleomormic adenoma was made. The patient was followed-up for a period of 1-year, and no evidence of recurrence was noticed [Figure 4]. Surgical excision of the swelling was carried out under general anesthesia.
|Figure 3: Photomicrograph showing epithelial and myoepithelial cells arrange in duct-like structures with mucin|
Click here to view
| Discussion|| |
Pleomorphic adenoma is the most common neoplasm of the salivary glands, mainly affecting mainly the parotid gland. However, it can also arise from minor salivary glands. When they occur in the minor salivary glands, the most common site is the palate because, the majority of the minor salivary glands are concentrated in the palate  followed by the lip, buccal mucosa, floor of mouth, tongue, tonsil, pharynx, retromolar area, and nasal cavity.  It has been also reported in nasopharynx and parapharyngeal space in rare instances. 
Pleomorphic adenoma may occur at any age, but the highest incidence is seen in 3 rd , 4 th and 5 th decades of life. Females (60%) had a higher incidence of pleomormic adenoma when compared to males. ,, Intraoral pleomorphic adenoma presents as a mobile slowly growing, painless, firm swelling. If the tumor is traumatised, secondary ulceration may occur.  The swelling in the 48-year-old patient was also firm and immobile. The lesion had a pointed area, but there was no discharge.
Histo-pathologically pleomorphic adenoma shows complex morphology, contains epithelial and myoepithelial elements arranged in various patterns and embedded in mucopolysaccharides stroma. Capsule formation is a result of fibrosis of the surrounding salivary parenchyma composed by the tumor that is referred to a false capsule. 
The treatment for pleomorphic adenoma in palate is wide local excision with the removal of periosteum or bone if it is involved.  Simple enucleation of this tumor can lead to high local recurrence rate and should be avoided.  Pleomorphic adenoma is known to produce a recurrence either due to rupture of capsule or tumor spillage, so meticulous dissection is important. Up to 44% of recurrence rate has been reported. 
The malignant transformation of the pleomorphic adenoma has been reported to occur in 2-7% of cases.  Distant meastasis of pleomorphic adenoma is rare.  There was no evidence of recurrence when the patient was recalled for a periodic check-up.
| Conclusion|| |
Pleomorphic adenoma is a benign salivary gland tumor most commonly seen in the parotid gland. It can also occur in minor salivary gland. Even though it is a benign tumour, it can hamper various functions in the oral cavity. Hence, early diagnosis and surgical excision results in complete cure with less or no morbidity.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]