Intraocular invasion of recurrent epibulbar malignant melanoma.

A case of a recurrent epibulbar naevus is presented; it underwent malignant transformation and subsequently invaded the eyeball. The tumour histologically was a predominantly epitheloid cell melanoma containing numerous histiocytes and degenerated tumour cells. Electron microscopy revealed rare special structures, e.g. annulated lamellae, tubuloreticular structures, pseudocrystals in huge mitochondria. Besides, invasion of tumour cells into a capillary could be shown.