Primary Oral Melanoma - A Non-Surgical Approach to Treatment via Immunotherapy

Malignant melanoma is an aggressive form of cancer that commonly affects skin and rarely affects the oral cavity. With poorly understood risk factors and an often-asymptomatic presentation, oral melanoma is difficult to detect until advanced stages of disease. Treatment for oral melanomas has been primarily surgical, and survival rates have been low. However, in recent years, immunotherapy has shown much promise with increased patient survival.

A 49-year-old male was referred by his primary dentist to a periodontal clinic for management of an alleged unresolved periodontal abscess. The patient had completed full-mouth scaling and root planing and consequently developed a large mass in the left posterior maxilla. Incisional biopsies were performed in multiple locations in the maxillary gingivae, and interpretation revealed atypical melanocytic proliferation and primary melanoma. After appropriate work-up, the patient was treated with two different immunotherapy agents: 1) ipilimumab and 2) pembrolizumab. Results after immunotherapy were favorable, and the tumor significantly decreased in size with no major adverse effects. The response was so strikingly positive that the need for surgical removal was almost eliminated. At the present time, it is unknown whether the patient will receive any surgical treatment barring a recurrence.

Oral mucosal pigmentation is a finding commonly encountered by dentists during clinical patient examinations. However, proper diagnosis of pigmented lesions, especially those associated with malignancy, requires investigations that go beyond clinical examination.