Basal Cell Adenoma of the Upper Lip: Report of a Rare Case With Literature Review

Basal cell adenoma (BCA) is a rare, benign tumor originating from the epithelial cells of the salivary glands. It was earlier categorized as a subtype of monomorphic adenoma with distinctive histopathological features. BCA usually manifests as asymptomatic, slow-growing masses that exhibit a site and age predilection, commonly affecting the major salivary glands of elderly female patients. Histologically, solid, trabecular, tubular, and membranous patterns are recognized. It is imperative to establish a precise distinction between BCA, pleomorphic adenoma, and malignant salivary gland tumors before initiating treatment to ensure effective management. The standard treatment approach is surgical resection of the tumor. Recurrence and malignant transformation rarely occur, except for the membranous subtype. This article aims to report an unusual case of BCA arising from a minor salivary gland in the upper lip. The post-operative course was unremarkable, with complete healing of the surgical site. No recurrence was observed during a one-year follow-up. BCA arising from a minor salivary gland in the upper lip is an extremely uncommon entity. A comprehensive review of BCA in the upper lip, reported from 1991 to December 2023, revealed only 14 cases.