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We retrospectively studied the nuclear RNA content in uveal melanomas with known, long-term follow-up. Thirty patients had spindle cell melanomas, 25 had mixed cell tumors, and 9 had epithelioid cell neoplasms. Epithelioid cell types had a higher nuclear RNA content compared to mixed or spindle cell types (p less than 0.05). Using the Cox proportional hazards model, the nuclear RNA content appeared to be an independent prognostic indicator in uveal melanomas, and an increased nuclear RNA content was associated with a worse prognosis (p = 0.001).

We observed a young woman who showed growth of a choroidal melanoma over the course of 2 pregnancies, with subsequent enucleation of the eye. This is the first such documented case. In addition 4 other women with uveal malignant melanomas presented during pregnancy. This observed number of pregnancies (5) was greater than the expected number (2.1) among women of childbearing age who underwent enucleation with subsequent analysis in our pathology laboratory. However, this difference was not statistically significant. Further, more females 44 years of age or younger underwent enucleation for malignant melanoma than men of comparable age. Evaluation of these cases led us to propose that there is a subset of patients whose ocular melanomas are hormonally responsive. We therefore analysed uveal melanoma and choroidal tissue from 7 patients, including one of the pregnant women, for the presence of oestrogen receptors. No specific oestrogen binding was found. The possibilities that other hormones are involved or an immunological mechanism is operative are discussed.

We performed experiments to determine the potential usefulness of nuclear magnetic resonance spectra in the diagnosis and follow-up of ocular melanoma. High-resolution phosphorus 31 nuclear magnetic resonance spectra at 109.3 MHz were obtained for human uveal melanoma, Greene hamster melanoma, and normal human diploid fibroblast cells. Phosphate metabolites were identified and their concentrations were shown to vary among the different cell lines. Uveal melanoma cells contain unusually high concentrations of the phospholipid metabolite phosphorylcholine and the phosphodiesters glycerol 3-phosphoryl choline and glycerol 3-phosphoryl ethanolamine. Baseline data are thus provided for studies of the effect of various treatment modalities on uveal melanoma. These initial results suggest that the data provided by high-resolution phosphorus 31 nuclear magnetic resonance spectra can provide useful diagnostic and follow-up data with respect to ocular melanoma.

Flow cytometry was used to evaluate ploidy and tumour cycle kinetics in fresh tissue samples obtained from 19 uveal melanomas. The results were compared with other parameters including, histological cell type, tumour size and anatomical location. Three tumours (15.8%) were aneuploid (two mixed cell, one epithelioid cell). Cell turnover was estimated in the 16 diploid tumours by summating the total percentage of cells in S and G2/M phases. We found the mean percentage of cells in G2/M/S to be 5.96% (range 2.2-9.8%). Spindle cell neoplasms appeared to have lower cell turnover rates (4.5 +/- 1.2%) than epithelioid cell turnover (8.4 +/- 1.2%). There was no correlation between cell turnover and either tumour size or anatomical location.

A perfusion culture system has been developed for 31P NMR study of human uveal melanoma metabolism by adapting the Vitafiber I cartridge system (Amicon). 31P NMR spectra collected weekly during periods of up to 10 weeks demonstrated increasing levels of phosphorus metabolites as the anchorage-dependent cells grew to tissue-like density.