Amyloid mass of the ciliary body.

Making the correct diagnosis of an iris–ciliary body tumor can be challenging. A 35-year-old woman sought care because of a growing amelanotic lesion that destroyed the iris root and produced a large ciliary body mass. She had a history of systemic lupus erythematosus. The tumor was completely removed with an iridocyclectomy, which revealed that the plasma cells had been producing a large amount of amyloid. To our knowledge, this is the first description of an amyloid lesion simulating a solid intraocular tumor. Amyloid involvement of ophthalmic structures is uncommon and rarely simulates a neoplasm. We and others have reported involvement of the vitreous in familial and nonfamilial primary amyloidosis; this process could be confused with an intraocular lymphoma. Similarly, there are several reported cases of conjunctival, eyelid, or orbital amyloid tumefactions. Rarely, amyloid can also be found infiltrating the anterior chamber angle or sclera, but no amyloid lesions simulating a solid intraocular tumor have been reported. The differential diagnosis of focal iris–ciliary body tumors is relatively straightforward. The majority of cases are uveal melanomas; less commonly, benign cystic lesions, melanocytomas, smooth muscle tumors, juvenile xanthogranuloma, Fuchs adenoma, primary carcinomas, medulloepitheliomas, lymphoid masses, neurofibromas, and metastases have been reported. We describe a unique case of a growing iris–ciliary body tumor that was shown, after excision with an iridocyclectomy, to be a plasma cell proliferation with a secondary amyloid deposit.