A Rare Case of Locally Advanced Malignant Melanoma of the Oral Tongue

Abstract

Introduction: The oral cavity is a rare location for the development of primary malignant melanoma. The most common primary lesion sites are the palate and gingiva. Cutaneous malignant melanomas constitute the majority of cases. Non cutaneous malignant melanomas are mainly seen in choroidal layer of the eye, mucosal surface of the upper respiratory tract, gastro-intestinal & genito- urinary tract.. Primary malignant melanoma originating in the oral cavity is a very rare entity ranging from 0.2% to 8.0% of all malignant melanoma cases. Case Presentation: A 60 year old female hindu patient from a rural background presented to our hospital with the complain of a dark coloured lesion in the tongue for 3-4 months. There were no cutaneous lesions suggestive of malignant melanoma over the rest of her body. The biopsy of the tongue lesion revealed a histopathology consistent with primary malignant melanoma which was further confirmed by immunohistochemistry.MR scan of tongue and neck was performed. Chest radiograph, abdominal sonography and computed tomography of chest and whole abdomen revealed no definite distal metastatic lesions. She received composite resection of the tumor on the right side of the tongue and right functional neck dissection followed by radiotherapy. Conclusion: The principle treatment for primary tongue melanoma is wide surgical excision. Early diagnosis will be promoted by careful oral examination and early biopsy of pigmented and non-pigmented masses. We reviewed the published reports in the English literature since 1970 and fewer than 30 cases of primary tongue melanoma were presented. We present a case report and a review of the relevant literature.