Retroauricular apocrine hidrocystoma: A very rare case report

Apocrine hidrocystoma is a rare benign cystic tumor arising from the secretory portion of the apocrine sweat glands. Although these lesions are typically found on the face, particularly at the eyelid margins, their occurrence in the retroauricular region is extremely rare, with four cases previously documented in the literature. We present the fifth reported case of a retroauricular apocrine hidrocystoma in a 29-year-old woman with a long-standing retroauricular lesion that remained stable for years before experiencing a rapid increase in size. We performed a magnetic resonance angiography that confirmed the cystic nature of the lesion followed by surgical excision under general anesthesia revealing histopathological findings consistent with apocrine hidrocystoma. This case highlights the importance of considering apocrine hidrocystoma in the differential diagnosis of retroauricular cystic lesions and the effectiveness of surgical excision in diagnosis and management.