Primary mucinous adenocarcinoma of the orbit: A rare clinical entity.

Primary mucinous adenocarcinoma is an exceptionally rare neoplasm with a propensity for local recurrence and metastasis. We report the second case in the world literature of a primary mucinous adenocarcinoma of the orbit in a 66-year-old man suffering from pain, progressive protrusion of left eye, and a deep drop in vision on the left for several weeks. His first external examination revealed significant proptosis with downward displacement of the left globe with no signs of lagophthalmos. A limitation of abduction was also noted. A CT of the orbit with and without contrast showed intra- and extra-conical solid expansive process. MRI of the orbit with contrast and without contrast has shown a process of the supero-internal angle of the left orbit. The patient was operated via a combined approach, and complete enucleation was done. The final pathologic diagnosis was mucinous adenocarcinoma of the orbit. The postoperative neuroimaging showed a complete resection of the tumor. The patient is referred for adjuvant radiotherapy. A CT of the orbit was made 3 months postoperatively and did not show any local recurrence.