Melanoma of External Auditory Canal: An Uncommon Entity

Introduction Malignant melanoma limited to external auditory canal (EAC) is very rare. Majority of patients present early, where a wide local excision with adequate margin is oncologically sufficient. But, in patients with advanced lesion, even multimodality treatment approach failed to prolong their survival. Local recurrences or distant metastases are not uncommon during follow-up period and have poor prognosis. We are reporting here a case of primary malignant melanoma of EAC that was treated successfully with limited surgery only.

Case presentation A 44-year-old female presented with ear discomfort, hearing impairment, and occasional bleeding from her left ear for 1 year. Examination revealed a blackish mass in her right external auditory canal almost occluding it, which was bleeding on manipulation. Radiology showed an enhancing mass limited to EAC at its opening without any bone erosion or nodal metastasis. Wide local excision of the mass was done under local anesthesia. Surrounding cartilage from the external auditory canal was excised and the base of the lesion was cauterized. The histopathology of the excised specimen showed features of malignant melanoma with invasion of basal layer of epidermis at places. The perichondrium and underlying excised cartilage were free of tumor involvement. Patient was further evaluated postoperatively to rule out any distant metastasis. She was kept under close observation and is disease free for past 4 years.

Discussion Malignant melanoma of ear constitutes 7 to 14% of all head and neck region melanomas. Early lesions are managed by wide local excision with negative margins. Melanoma with thickness more than 4 mm, with bone erosion, with regional spread have very poor prognosis even with multimodality treatment. In our case, the tumor was very limited and underlying cartilage was free, which is a barrier to tumor spread. So, only local excision was sufficient.

Conclusion Ear melanoma involving the external auditory canal has variable presentation. Although the outcome in advanced diseases is very poor, but when presented early, shows better prognosis and longer survival. Thus, early diagnosis is the key for better outcome, and extensive surgery is usually not needed in every case as was the initial protocol.