Non-familial Multiple Trichoepithelioma: A Case Report

Trichoepithelioma is a well-differentiated benign follicular tumour. Clinically, it may either be solitary or multiple. Multiple trichoepitheliomas are often located on the face and its vicinity. Here, we present this case due to the increasing number of lesions over ten years, particularly with the lesions blocking the external auditory canal. This case is presented with clinical, histopathological and immunohistochemical features, with differential diagnoses. The patient was a 70-year-old female with localised papules on the external auditory canal, ear lobule, tragus, neck and lower lip. The microscopic examination of the excisional biopsy from the external auditory canal revealed a tumoural formation surrounded with stromal fibrosis and mononuclear infiltration, which is composed of basaloid cells showing peripheral palisading and keratinocytes with infundibular keratinisation. Upon immunohistochemical studies, the surrounding stroma of the tumour showed diffuse cytoplasmic positivity for CD34, and focal cytoplasmic positivity for BerEP4. There was no significant family history in this case. This pathology must be kept in mind in the differential diagnosis of tumours of the epidermis and skin appendages which occur on the face and its vicinity.