A Case of Squamous Cell Carcinoma Occurred in the External Auditory Canal Misdiagnosed as a Keratoacanthoma after Radiotherapy for Kimura's Disease / 대한이비인후과학회지

ABSTRACT

Malignancy of the external auditory canal (EAC) is a rare tumor. Among the malignancies of EAC, squamous cell carcinoma (SCC) is the most common pathologic type. The causes of SCC of EAC may be exposure to ultraviolet rays, cholesteatoma, chronic otitis externa, and rarely radiotherapy. SCC of EAC has the diverse and non-specific clinical features including mass of tissue, otorrhea, otalgia, tinnitus, and facial palsy which make it difficult to distinguish between SCC and benign tumor. Recently, we experienced a case of SCC of EAC occurred in the left external auditory canal after radiotherapy for Kimura's disease, which was misdiagnosed as keratoacanthoma at first. The findings of this case suggest that when it is difficult to distinguish SCC from benign tumor of EAC, the excisional biopsy including enough resected margin and base of tumor is needed for an exact diagnosis.