The correlation between cell surface markers and clinical features in choroidal malignant melanomas

Purpose Uveal melanoma continues to present problems when attempting to pre dict disease progression. This study attempts to identify markers indicativ e of the biological characteristics of cells isolated from samples of uveal melanoma, including adhesion (ICAM-1), immune reactivity (MHC Class I and II), cell cycle control (c-erbB-2, c-myc) and apoptosis control (bcl-2, p53 ) using dual parameter (DNA/MoAb) flow cytometry. Methods Sixty-three fresh tissue samples from choroidal melanomas were take n at enucleation. Samples were assayed for DNA content and cell, cycle, the above antibodies together with positive (PHM-5) and negative (2 degrees FI TC Ab) controls. The clinical parameters sex, age, tumour location, cell ty pe, tumour volume and presence of metastases were compared with the results and analysed with the non-parametric Mann-Whitney U-t-test. Results ICAM-1 expression proved to be the most clinically relevant, being present on a higher proportion of cells in tumours >2000 mm(3) (median 38, n = 19) compared with the smaller tumours <2000 mm(3) (median 17, n = 26) ( p = 0.0015). Metastatic disease was present in 11 patients and did not corr elate with any of the surface markers. C-myc, c-erbB-2 and MHC Class II exp ression were associated with cell type, all showing greater expression in s pindle cell tumours than mixed/epithelial types. Conclusion These results show flow cytometry as a quick, easy method to pro vide a 'phenotypic profile' for these tumours, and identifies cell cycle co ntrol and adhesion molecule expression as important areas for further inves tigation. c-erbB-2 and bcl-2 positivity was typically seen on over 60% cell s in each sample, indicating two potential targets for therapeutic interven tion.