RESUMEN
A case of apocrine adenocarcinoma of the eyelid that showed unusually aggressive biological behavior is reported. The patient was a 57-year-old man who complained of discomfort and excessive lacrimation of the left eye. A subcutaneous tumor measuring 2.5 cm was found at the medial canthus of the upper eyelid, and a plica-like subconjunctival spread was noted in the lacrimal caruncle. Invasion into the extraocular muscles and metastasis to the cervical lymph nodes and bone were already present at the time of initial presentation. Histopathologically, the tumor showed features of poorly differentiated adenocarcinoma, and polygonal tumor cells had large, hyperchromatic nuclei with prominent nucleoli and abundant eosinophilic cytoplasm. The formation of ductal structures was found occasionally. The differentiation of the tumor cells towards the apocrine gland was corroborated by immunohistochemistry using monoclonal antibodies GCDFP-15 and B72.3. The histogenesis and pathological differential diagnosis are discussed briefly, and the tumor was considered to have originated in the Moll's gland in the eyelid. This case emphasizes that apocrine adenocarcinomas of the ocular region have the potential for aggressive biological behavior, including distant metastasis.