Intradermal nevus of the external auditory canal.

Melanocytic nevus is a benign melanocytic neoplasm and the most common type of skin tumor. Melanocytic nevus in the external auditory canal (EAC) is rare. Surgical excision and pathologic confirmation should be considered in large lesions, which could occlude the EAC, or atypical lesions that are suspicious for malignancy.

A 36‐year‐old woman visited the otorhinolaryngologic clinic for right otalgia without hearing impairment several months in duration. She had no history of excessive sunlight exposure to the external auditory canal (EAC). A 0.7 × 0.7‐cm, firm, non‐tender, nodular mass was observed in the anteroinferior portion of the right EAC (Figure 1). The lesion was excised completely. Intradermal nevus was diagnosed histopathologically (Figure 2).

FIGURE 1

0.7 × 0.7‐cm, firm, non‐tender, nodular mass in the anteroinferior portion of the right external auditory canal

FIGURE 2

In histopathology, clusters of nevus cells in the dermis without junctional activity, diagnosing intradermal nevus (hematoxylin–eosin, ×40)

Melanocytic nevus can be divided into junctional, intradermal, and compound nevus according to nevus cell cluster site. , Melanocytic nevus in the EAC can cause symptoms such as ear fullness, foreign body sensation, hearing impairment, and otalgia. Large melanocytic nevus in the EAC can occlude the EAC and induce accumulation of wax and desquamated keratin causing EAC cholesteatoma. ,

Malignant melanoma is the most important differential diagnosis. Malignancy should be suspected if there are recent rapid growth, irregular border, shades of brown and black, or increased numbers and size of nevi.

What is the probable diagnosis based on this image? This image emphasizes that melanocytic nevus can be observed in the EAC. Although observation is sufficient in most asymptomatic cases, surgical excision and pathologic confirmation should be considered in large lesions causing symptoms, or atypical lesions suspicious for malignancy.

CONFLICT OF INTEREST

None declared.

AUTHOR CONTRIBUTIONS

JJ involved in conceptualization, data collection, literature review, analysis, investigation, writing–original draft, review, and editing. EKK involved in data collection, analysis, and investigation.

ETHICAL APPROVAL

The Institutional Review Board of the National Health Insurance Service Ilsan Hospital exempted the review of this study (NHIMC 2021‐12‐006).

CONSENT

Written informed consent was obtained from the patient to publish this report.