A 56-year-old man presented with a left ciliary body mass, anterior vitreous hemorrhage and a subluxed, cataractous lens. The clinical course included rapid enlargement of the mass, anterior uveitis, cataract progression and secondary glaucoma. Investigation included fluorescein angiography, ultrasonography and computed tomography. The eye was enucleated because of progressive enlargement with poor vision and uncontrolled secondary glaucoma. Histopathological examination showed an adenoma of the nonpigmented ciliary epithelium with cystic areas of hyaluronidase-sensitive acid mucopolysaccharide. The mass distorted the iris, occluded the angle structures and produced a complete cataract. The basement membrane of the adjacent ciliary processes was extensively thickened. The authors discuss the clinical association with vitreous hemorrhage and the local damage caused by this benign tumour.