Asian Journal of Case Reports in Surgery

Background: Minor salivary gland tumours account for 22% of all salivary gland neoplasms. Only eighteen per cent of them are benign; the majority of them are malignant. In about 8% of cases, pleomorphic adenomas affect minor salivary glands, with rare occurrences in the upper gingivobuccal sulcus (GBS).

Case Presentation: The case of a 31-year-old male with a pleomorphic adenoma located in the right upper GBS, presenting as a swelling measuring 3x2x2 cm, was reported. The lesion was surgically excised, and the postoperative biopsy confirmed the diagnosis of pleomorphic adenoma with clear margins.

Discussion: Among the differential diagnoses of pleomorphic adenoma of buccal mucosa are lipoma, neurofibroma, dermoid cyst, sebaceous cyst, buccal abscess, mucoepidermoid carcinoma and low-grade polymorphous adenocarcinoma. These neoplasms, although slow-growing, can exhibit significant growth if not treated and may undergo a rare malignant transformation into carcinoma ex pleomorphic adenoma. Because of their rare potential to develop into more aggressive cancers like adenoid cystic or mucoepidermoid carcinoma, as well as their elevated risk of recurrence (approximately 13 per cent), minor salivary gland neoplasms need to be regularly monitored.

Conclusions: This case emphasises the importance of considering pleomorphic adenoma in the differential diagnosis of oral lesions, even in atypical locations, and highlights the value of surgical excision for treatment and definitive diagnosis.