Abstract
Eccrine hidradenoma (acrospiroma) is a benign adnexal neoplasm with eccrine and probable apocrine derivation. Atypical hidradenoma and hidradenocarcinoma are rare and challenging to diagnose. A 22-year-old female with history of anemia, eczema, obesity, and dysmenorrhea presented with a large pedunculated lesion attached to her left lower eyelid. The lesion grew rapidly during the last year after being stable for five years. CT scan revealed a cutaneous/subcutaneous mass with a stalk at the left infraorbital preseptal soft tissue without involvement of the orbit and the maxillofacial osseous structures. Biopsy was performed and demonstrated a skin adnexal neoplasm, favoring hidradenoma. The lesion was later entirely excised with clear margins. The specimen showed a globular circumscribed tumor measuring 4.2 x 3.0 x 1.8 cm. The highly cellular tumor was composed of polygonal cells and clear cells with minimal nuclear pleomorphism and interspersed prominent mucinous metaplasia. The tumor cells extended from the surface epidermis into the dermis, arranged in trabecular and solid growth patterns. Increased mitosis was present focally (up to 8 mitotic figures/10 HPF) without necrosis. Focal ductal differentiation was highlighted by positive diastase-resistant PAS stain and EMA immunostain (Fig-1- A-D, H&E, EMA, mucicarmine, Ki67). The tumor was found to harbor t(11,19) (q14-21; p12-13) translocation resulting in the CRTC1-MAML2 fusion gene. The patient has been followed up for eight months with no tumor recurrence. To our knowledge, this is the first report of atypical hidradenoma occurring in an eyelid with unusual features including prominent mucinous metaplasia, exceptionally high mitotic figures and CRTC1-MAML2 translocation.
Financial Disclosure:
No current or relevant financial relationships exist.