Background: Myxomas are rare benign tumors that can be found most frequently in the heart. We report the clinical and histological findings in a very rare case of corneal myxoma, which is only the sixth case in the literature.
Case: A whitish elevated tumor of the anterior cornea developed in the left eye cornea of a 46-year-old man 2 years after luxation of the patient's lens into the anterior chamber and subsequent endothelial decompensation. The tumor covered the entire surface of the cornea except for the outer limbal periphery at Schwalbe's line.
Observations: Histologically, the hypocellular tumor was characterized by scattered spindle- and stellate-shaped cells with wavy, randomly oriented collagen fibers in a myxomatous ground substance staining positively for acid mucopolysaccharides. Bowman's layer was absent. Immunohistochemically, the tumor cells were positive for vimentin. Ultrastructurally, the tumor cells had features characteristic of keratocytes with no basement membrane, much rough endoplasmic reticulum and vacuoles containing mucoid-like material.
Conclusions: The ultrastructural observations support the hypothesis of a cellular origin of the myxoma from keratocytes. The tumor growth was most probably stimulated by chronic endothelial failure and bullous keratopathy.