DNA content abnormalities and prognosis in uveal melanoma
W. J. Meecham and D. H. Char
Recent advances in flow cytometry allow for study of DNA content in
paraffin-embedded pathology material. Using refinements of published
techniques, we retrospectively correlated tumor cell DNA content (ploidy)
with histologic findings and clinical outcome in 79 patients with uveal
melanoma. Patients were included using these selection criteria:
enucleation without adjunctive therapy performed at the University of
California at San Francisco between 1956 and 1979, tumor located in ciliary
body or choroid, and pathology material and complete follow-up data
available. The DNA histograms were classifiable as diploid or hyperploid in
64 cases. The mean coefficient of variation for diploid histograms was
6.6%. Twenty-three patients (36%) had hyperploid tumors. Hyperploidy was
correlated with worse outcome. The effect was most marked for DNA indexes
of over 1.4. A Cox proportional hazards model showed that the effects of
tumor diameter and cell type were insignificant in comparison with the
effect of the DNA index.
