Mucosal melanoma of the oral cavity

Abstract

Primary mucosal melanomas of the head and neck region are uncommon but aggressive malignancies. These lesions arise from melanocytes located in mucosal membranes, predominantly in the nasal cavity, paranasal sinuses, and oral cavity. Mucosal melanomas account for less than 4% of all melanoma cases and are often missed, due to their occult initial presentations. This is in contrast to cutaneous melanomas, which constitute approximately 85% of melanoma cases and present on surfaces exposed to ultraviolet (UV) radiation. The mainstay of treatment for mucosal melanoma is surgical resection with adjuvant radiotherapy for patients with high-risk features. Despite advancements in surgical techniques, radiotherapy, and even systemic therapies, patients with mucosal melanoma face unfavourable prognoses (5-year disease-free survival <25%) with high rates of locoregional recurrence and/or distant metastases. The present case addresses a 47 year-old man who presents to Otolaryngology with an apparent mucosal melanoma involving the upper lip. This patient was informed of a pigmented lesion on the mucosal surface of the upper left lip three years prior by his dentist. Although largely asymptomatic, the lesion has increased in size. The patient undergoes surgical resection with clear margins and reconstruction. He continues to follow-up to monitor for disease recurrence, having denied adjuvant radiation. This case illustrates the diagnosis and approach to mucosal melanomas and highlights some of the key distinctions between mucosal and cutaneous melanomas.