Hidrocystoma on the auricular helix in a female patient: a case report and literature review

Hidrocystoma is a benign tumor arising from the cystic proliferation of apocrine or eccrine sweat glands.It is often asymptomatic and most commonly found in the periorbital region, although it can develop wherever sweat ducts are abundant.We report the case of an 84-year-old woman who presented with a 1 cm normochromic nodule on the helix of her left ear, of 5 months' duration, showing intermittent size fluctuations and no associated symptoms.An excisional biopsy was performed, and hematoxylin-eosin staining revealed a unilocular cystic structure lined by a double-layered epithelium exhibiting cytoplasmic decapitation and intraluminal secretory material, confirming apocrine differentiation.The histological findings were consistent with an apocrine hidrocystoma in an auricular location -a presentation that is rare in the literature.The patient was counseled regarding the benign nature of the lesion and scheduled for clinical follow-up.This case highlights the importance of considering hidrocystoma in the differential diagnosis of translucent nodules occurring in extrapalpebral or facial regions.