Primary Malignant Melanoma of Tongue: Rare and Aggressive Malignant Tumor

Primary melanoma of the oral cavity is extremely rare, accounting for 0.2-8% of all melanomas. Lesions arising from mucosal melanocytes occur most frequently on the gingiva or palate. Mucosal melanomas carry a worse prognosis than cutaneous melanomas. Very few studies have been published due to rarity of disease. 46 year old lady presented with black colored lesion over left side of her tongue for 6 weeks. On examination there was 3 × 2.5 cm black colored patch over left lateral part of tongue in middle 1/3rd, not crossing midline. Tip and base of tongue were free. Biopsy was suggestive of malignant melanoma of tongue. Patient underwent surgery (wide local excision of left lateral border of tongue lesion + left selective neck dissection). Final Histopathological report revealed malignant melanoma of tongue with all margins free, Depth of invasion 3 mm, Lympho-vascular invasion present, and no perineural invasion, left level III cervical lymph node metastases. Patient thus received adjuvant RT. Immunotherapy was also advised in multidisciplinary clinic, but patient was non-compliant. Early diagnosis will be promoted by careful oral examination and early biopsy of pigmented and non-pigmented masses. Early diagnosis and treatment will improve the prognosis of patients with oral malignant melanoma.