Pleomorphic Adenoma of Minor Salivary Gland in the Upper Lip: A Case Report of a Common Neoplasm in a Rare Site

Introduction: Pleomorphic adenoma (PA) is the most common benign salivary gland neoplasm, accounting for approximately 60% - 70% of all salivary gland tumors. Although it predominantly affects the major salivary glands, 10% - 15% of cases arise from minor salivary glands, most commonly in the palate, while involvement of the upper lip remains uncommon. Clinically, PA presents as a slow-growing, painless, well-circumscribed submucosal mass and requires histopathological confirmation for definitive diagnosis. We report a rare case of pleomorphic adenoma of a minor salivary gland of the upper lip, highlighting its diagnostic challenges and surgical management. Aim: To present a rare clinical case of a Pleomorphic Adenoma of Minor Salivary Gland located in the upper lip and its management. Case Report: A 45-year-old male patient presented with a painless swelling of the left upper lip that had been evolving over a period of three years. The lesion was slowly growing, firm in consistency, and was not associated with ulceration of the overlying mucosa. Magnetic resonance imaging (MRI) revealed a well-circumscribed, oval-shaped lesion of the left upper lip measuring 23 × 18 × 18 mm. The lesion was solid-cystic in appearance, demonstrated heterogeneous isointense signal on T1- and T2-weighted sequences, and was surrounded by a T2 hypointense capsule. It showed no diffusion restriction and exhibited heterogeneous enhancement following gadolinium administration. Surgical excision was performed under local anesthesia. Histopathological examination confirmed the diagnosis of pleomorphic adenoma. This case highlights the importance of considering this entity in the differential diagnosis of longstanding, indolent intraoral swellings. Conclusion: Pleomorphic adenoma of the upper lip is an uncommon presentation of a common salivary gland neoplasm. Careful clinical assessment, imaging, and histopathological examination are essential for accurate diagnosis. Complete surgical excision remains the treatment of choice and is associated with an excellent prognosis and a low risk of recurrence.