Hidradenoma papilliferum of the caruncle: a case report.

Hidradenoma papilliferum (HAP) is a rare benign adnexal tumor of apocrine differentiation, typically occurring in the vulvar or perianal region of women. We report an exceptionally rare case of HAP arising from the lacrimal caruncle, with only one similar case previously documented in the ophthalmic literature. A 61-year-old woman presented with a 3-month history of a painless, vascularized reddish mass over the right caruncle. Complete surgical excision was performed without complications. Histopathological examination revealed a well-circumscribed lesion with papillary and glandular architecture, fibrovascular cores, and a characteristic bilayered epithelium with apocrine features, consistent with HAP and without evidence of malignancy. This case highlights the importance of considering HAP in the differential diagnosis of caruncular tumors and confirms surgical excision as curative.