|Year : 2015 | Volume
| Issue : 2 | Page : 117-120
Pleomorphic adenoma of minor salivary gland in the cheek
NT Geetha, BV Deepa, KV Umashankara, Rai Kithikumar
Department of Oral and Maxillofacial Surgery, Bapuji Dental College and Hospital, Davangere, Karnataka, India
|Date of Web Publication||10-Mar-2016|
Dr. N T Geetha
Department of Oral and Maxillofacial Surgery, Bapuji Dental College and Hospital, Davangere, Karnataka
Source of Support: None, Conflict of Interest: None
The pleomorphic adenoma comprises the majority of both major and minor salivary gland tumors accounting for 3–10% of neoplasms of head and neck region. The palate is the predominant intraoral site, and the mucosa of the cheek is an uncommon site for these tumors. These minor salivary gland pleomorphic adenomas require diagnosis based on clinical features and incisional biopsy should be avoided. These are managed by wide surgical excision. The recurrence of this tumor is a well-known factor, and inadequate initial surgical procedure is the most common cause of recurrence. Carcinoma arising from pleomorphic adenoma accounts for about 3% of salivary tumors. Recurrence rates and malignant transformation of this tumor cells for long-term follow-up of these cases. We are reporting a case of pleomorphic adenoma in the left buccal mucosa in a 48-year-old female patient.
Keywords: Buccal gland, minor salivary gland, pleomorphic adenoma
|How to cite this article:|
Geetha N T, Deepa B V, Umashankara K V, Kithikumar R. Pleomorphic adenoma of minor salivary gland in the cheek. Int J Oral Health Sci 2015;5:117-20
| Introduction|| |
Salivary gland tumors are uncommon and constitute 2–6.5% of all the head and neck neoplasms. Tumors of the minor oropharyngeal salivary glands account for <25% of the total salivary neoplasms. The palate, the upper lip, and the buccal mucosa are the predominant intraoral sites for these minor salivary gland tumors., The pleomorphic adenoma comprises the majority of both major and minor salivary gland tumors accounting for 3–10% of neoplasms of head and neck region. The mucosa of the cheek is an uncommon site of occurrence for intraoral pleomorphic adenoma.
“Pleomorphic adenoma” is a term suggested by Willis because of its unusual histological pattern. It is not a mixed tumor, as it is not teratomatous or derived from more than one primary tissue. The morphogenic complexity is because of differentiation of the tumor cells into fibrous, hyalinized, myxoid, chondroid, and even osseous tissue. Patients with pleomorphic adenomas of minor salivary glands usually present in the fourth to sixth decades with a slight predominance in female patients. About 5–10% of these minor salivary gland pleomorphic adenomas affect patients aged 20 years and under, the majority occurring in the second decade of life. Cases have been reported in patients as young as 3 months up to 18 years.,, Here, we report a case of pleomorphic adenoma of the cheek in a 48-year-old female patient.
| Case Report|| |
A 48-year-old female patient came to our department with the chief complaint of swelling and pain in her left buccal mucosa for 10 days. There was no facial asymmetry. Intraoral examination revealed a 1.5 cm × 3 cm well-circumscribed, mobile, firm, solitary mass with some fluctuance over the left buccal mucosa posterior to the parotid ductal opening. The mucosa over the mass was ulcerated [Figure 1]. The salivary flow from parotid duct was examined and found to be normal. The ulceration was due to the chronic irritation from the left maxillary first molar, which she got extracted 4 days back in a private clinic because of the impingement of the first molar on the buccal mucosa causing ulceration over the area. The patient does not give any history of previous swelling or ulceration of similar kind in the same region.
The tumor was excised via intraoral approach under local anesthesia. Parotid duct was avoided, and the mass was found to lie between the buccal mucosa and buccinator muscle [Figure 2]. After meticulous dissection, the lesion was freed from the surrounding tissue and was removed along with an adequate margin of normal tissue. The mass had a thin capsule, and the wound was closed primarily [Figure 3].
Histologic examination showed subepithelial connective tissue composed of glandular epithelium and myoepithelial cells arranged in the form of ducts and sheets in a myxomatous background. There was also the evidence of hyalinized and chondroid areas, and focal inflammatory infiltrates chiefly consisting of lymphocytes and plasma cells [Figure 4]. These features were suggestive of pleomorphic adenoma. Postoperative period was uneventful. Patient is under regular follow-up.
|Figure 4: Pictomicrograph showing the myoepithelial cells arranged in the form of ducts and sheets along with the chondroid and hyalinized areas in the myxomatous stroma|
Click here to view
| Discussion|| |
Pleomorphic adenoma is the most common minor salivary gland tumor accounting for about 33–70% of all tumors and 70.6–100% of benign tumors. The palatal glands are the most commonly affected with pleomorphic adenoma with a frequency ranging from 43% to 70% followed by the upper lip (10.1%) and cheek (5.5%). Other rare sites include the throat (2.5%), retromolar region (0.7%), floor of the mouth, and the alveolar mucosa.,,, The pleomorphic adenomas in the buccal mucosa are known to arise from the submucosal buccal minor salivary glands. However, they are even known to arise from the glands located in the buccal space external to buccinator known as molar or buccal glands.
This tumor usually presents as a unilateral, painless, slow growing mass in the parotid gland. Few cases are also reported as ulceration, pain, and bleeding., The pleomorphic adenomas in youngsters will have similar biological characteristics as in adults but with low recurrence rates after surgical excision. In our case, it was presented as a swelling associated with an ulcer over the buccal mucosa. The differential diagnosis of minor salivary gland pleomorphic adenoma of the cheek includes buccal space abscess, hemangioma, dermoid cyst, lipoma, neurofibroma, rhabdomyosarcoma, mucoepidermoid carcinoma, adenoid cystic carcinoma, carcinoma ex pleomorphic adenoma, and foreign body reaction. Abscess was ruled out because of the absence of signs of infection, hemangioma was ruled out by the absence of any bleed even after ulceration. Dermoid cyst or lipoma was ruled out as there was no fluctuance. Malignancy was ruled out as there was no induration or fixity to underlying tissues.
Histologically, these tumors will have epithelial cells arranged in cord or duct-like cell patterns, along with epidermoid metaplasia. The intercellular matrix shows fibrous, hyaline, myxoid, cartilaginous, and osseous areas. Myoepithelial cells or ductal reserve cells are responsible for such pleomorphic extracellular matrix production. Histologic variants of pleomorphic adenoma include pleomorphic adenoma with lipomatous change, myxolipomatous pleomorphic adenoma, pleomorphic adenoma with squamous differentiation, and benign metastasizing mixed tumor.
Treatment of pleomorphic adenoma includes simple excision, excision with a margin, and use of adjuvant radiotherapy. Many pleomorphic adenomas of minor salivary glands will have a capsule that is either thin or incomplete., Though these benign tumors are encapsulated, they require resection with an adequate margin of normal surrounding tissue because these tumors are known to have microscopic pseudopod-like extensions into the surrounding tissue due to dehiscences in the false capsule. Hence, incisional biopsy is avoided in these tumors to avoid spillage of the tumor cells. The recurrence of this tumor is a well-known factor. Lou et al. reported a recurrence of 7% in 1342 patients with benign parotid neoplasms and 6% in benign minor salivary gland tumors. Recurrences are reported even at 18 years after initial treatment., Inadequate initial surgical procedure was reported to be the main cause of failure. Pseudopodia, capsular penetration, and tumor rupture with spillage of tumor cells are the most frequently encountered surgical issues. If we consider its malignant potential, in a series of 737 minor salivary gland tumors, Wang et al. found 53.9% to be malignant. Carcinoma arising from pleomorphic adenoma accounts for about 3% of salivary tumors. In recent years, immunohistochemical markers are playing a major role in distinguishing pleomorphic adenomas from malignant salivary gland tumors. Human epidermal growth factor receptor-2/neu expression, androgen receptor expression, overexpression of P53, and expression of Ki-67 can be used in evaluating malignant salivary gland tumors, but these markers may also be expressed in benign pleomorphic adenomas. Hence, in the absence of compelling histologic features of malignancy, expression of these immunohistochemical markers should not be interpreted as evidence of carcinomatous transformation in a pleomorphic adenoma.
| Conclusion|| |
Pleomorphic adenoma of the cheek is a rare neoplasm. It needs to be diagnosed with a proper history and clinical examination. Wide surgical excision with a margin of surrounding tissue is the treatment of choice. Recurrence even after many years of surgical excision as well as malignant transformation should be a concern, and, therefore, long-term follow-up of these cases is advisable.
We would like to thank Dr. Ahmed Mujeeb, Professor, and Head of the Department, Department of Oral Pathology and Microbiology, Bapuji Dental College and Hospital, Davangere, Karnataka for histopathological guidance.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Eveson JW, Cawson RA. Tumours of the minor (oropharyngeal) salivary glands: A demographic study of 336 cases. J Oral Pathol 1985;14:500-9.
Waldron CA, el-Mofty SK, Gnepp DR. Tumors of the intraoral minor salivary glands: A demographic and histologic study of 426 cases. Oral Surg Oral Med Oral Pathol 1988;66:323-33.
Toida M, Shimokawa K, Makita H, Kato K, Kobayashi A, Kusunoki Y, et al.
Intraoral minor salivary gland tumors: A clinicopathological study of 82 cases. Int J Oral Maxillofac Surg 2005;34:528-32.
Wang D, Li Y, He H, Liu L, Wu L, He Z. Intraoral minor salivary gland tumors in a Chinese population: a retrospective study on 737 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2007;104:94-100.
Jorge J, Pires FR, Alves FA, Perez DE, Kowalski LP, Lopes MA, et al.
Juvenile intraoral pleomorphic adenoma: Report of five cases and review of the literature. Int J Oral Maxillofac Surg 2002;31:273-5.
Mubeen K, Vijayalakshmi KR, Pati AR, Giraddi GB, Singh C. Benign pleomorphic adenoma of minor salivary gland of palate. J Dent Oral Hyg 2011;3:82-8.
Varghese BT, Sebastian P, Abraham EK, Mathews A. Pleomorphic adenoma of minor salivary gland in the parapharyngeal space. World J Surg Oncol 2003;1:2.
Pillai AK, Satpathy M, Nahar S, Moghe S. Pleomorphic adenoma in cheek: An uncommon finding. IJSS Case Rep Rev 2014;1:19-22.
Lou SM, Rich AM, De Silva RK, Ferguson MM. Pleomorphic adenoma of minor salivary gland. Oral Oncol Extra 2006;42:170-2.
Tom C. DeRoche, Aaron P. Hoschar, Jennifer L. Hunt. Pleomorphic Adenomas: An Immunohistochemical Study. Arch pathol lab med. 2008; 132: 1907-11.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]