[A case of pleomorphic adenocarcinoma of the ciliary body]

We performed local resection of a ciliary body tumor, which was diagnosed as pleomorphic adenocarcinoma arising from nonpigmented epithelium of the ciliary body. The patient was a 57-year-old male, and the tumor was found incidentally at an ophthalmologic examination. Since the possibility of malignant tumor could not be ruled out, local resection of the tumor was performed. The tumor developed from the pars plicata and the size was 5.5 x 6.0 x 7.5 mm. Histologically, the tumor cells displayed heteromorphism and revealed tubular and glandular structures which continued to the ciliary body epithelium. Melanin pigment was not observed, except in one small area of the tumor. The interstitium of the tumor tissue was stained with alcian blue, and a immunohistochemical study showed that tumor cells were positive for epithelial membrane antigen (EMA) and vimentin, but negative for S-100 protein and carcinoembryonic antigen (CEA). Electron microscopy revealed desmosomes between cells, and microvilli were observed at the margin of the glandular cavity structure. In this case, no severe complications occurred even after local resection and good visual function was maintained.