並列摘要
Pilar sheath acanthoma is a type of rare, benign tumor of the skin hair follicle and usually locates in the head and neck region. In 1978, Mebregan and Brownstein first reported several cases. Clinically, this tumor is a painless, skin-colored nodule with a central cavity containing accumulated keratinous material. It is often located on the upper lip or the face. In March of 2003, a middle-aged woman presented with a small, solitary nodule on the rim of her right nostril. After excision biopsy, the nodule showed histological characteristics typical of pilar sheath acanthoma. We present this case because reports of pilar sheath acanthoma have been rare in the otolaryngology literature over the past 20 years, and this tumor is occasionally difficult to differentiate from other skin hair follicle lesions.