Cytogenetical observations in nine ocular malignant melanomas.

The cytogenetical findings in one conjunctival and eight uveal melanomas are reported. Six of the intraocular tumors displayed clonal abnormalities. In two of these cases there were both extensive numerical and structural aberrations. Only the single ciliary body melanoma showed the deviations monosomy 3 and gain of 8q considered typical of uveal melanomas. No preferential pattern could be discerned for the clonal abnormalities in the other uveal melanomas. The one conjunctival tumor, arising in an area of precancerous melanosis, showed only a small clone with a 4q+marker. The clonal abnormalities in the nine cases showed no similarities to those on record for cutaneous melanomas.