Oncocytic adenocarcinoma of lacrimal gland with GCDFP15 positivity

Abstract

Abstract Purpose: We present a very rare case of an oncocytic adenocarcinoma of the lacrimal gland. In our case it seems to arise from an oncocytoma and there is an interesting immunophenotype of this tumour, since it appears positive for the GCDFP 15 protein, which has not been described before. Methods: A 77‐year‐old woman presented to the ophthalmologist, complaining of a six‐month history of pains at the left canthus. Incisional biopsy showed an epithelial oncocytic neoplasm which was reviewed in a tertiary ophthalmic pathology centre, where a immunohistochemistry revealed positivity for CK7 and GCDFP15 (PIP), with negativity for OR(ER), CK20, HepPar1, AFP, CA19‐9, TTF, S100, chromogranin and synaptophysin. Results: After excluding the possibility of metastasis from a non‐ocular/adnexal primary neoplasm, she underwent left orbital exenteration. Pathological examination showed an aggressive oncocytic adenocarcinoma involving the lacrimal gland and containing a small focus of what appeared to be oncocytoma. The immunophenotype was similar to the original biopsy. Electron microscopy confirmed large numbers of mitochondria present within the tumour cells. Conclusions: We reviewed the ophthalmic literature for previous reported oncocytic adenocarcinomas. Our case is different in that there is a very interesting immunohistochemical profile with a strong positivity for gross cystic disease fluid protein 15 (GCDFP15), which has never been described before in oncocytic lesions of the lacrimal gland. An interesting theory would correlate the fact that both organs (breast and lacrimal gland) derive from ectoderm, but this correlation needs to be thoroughly investigated.