Five cases of uveal malignant melanoma are reported by light and electron microscopy. The tumors are located in the iris (one case), in the choroid (three cases), in the uvea (one case). By light microscopy they are classified according to Callender cell - types as follows: - fusiform B in two cases (iris and choroid), - epithelioid in two cases (choroid), mixed in one case (uvea). By electron microscopy the various types of malignant melanoma do not appear as clearly as by light microscopy: the cell polymorphism of the tumor, in a same type, seems related to the proliferation of various malignant ‘cell- clones’. Malignant criteria observed in tumor cells allow to bring together uvea and skin malignant melanomas without identifying them. The authors stress the impossibility to precise the origin of malignant pigmented tumor cells in uveal melanomas and skin melanomas as w
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