For uveal melanoma it has been shown that nuclear DNA content (ploidy) abnormalities correlate closely with survival,1-4 although conflicting results have been reported for older archival material,5 fresh tissue,6 and differences in DNA quantification techniques.7 A significant correlation between aneuploidy and epithelioid cell type has been reported2 3 8; other studies indicate similar findings,9 or contradict these findings.4 In this issue of the BJO (p 1433) Toti et al report conflicting results on the prognostic value of aneuploidy and association of aneuploidy with epithelioid cell type in uveal melanoma. Furthermore, they found a remarkably high incidence of hypodiploidy.

Methods for ploidy analysis include flow cytometry (FCM), static image analysis (IA), and—more recently—the cytogenetic approach. Each ploidy analysis has its own advantages and disadvantages, many of which reflect the reported conflicting results.10 11 Ploidy analysis by FCM and IA has been reported for uveal melanoma.1-9 12 13 Both methods plot the cells at the different …