S-100B protein and melanoma inhibitory activity protein in uveal melanoma screening. A comparison with liver function tests.

Abstract

AIM: Our purpose was to determine whether S-100B or melanoma inhibitory activity (MIA) concentrations in the serum of patients with large uveal melanomas were better markers for the presentation of metastases than liver function tests. We also investigated whether increased marker levels were related to known clinical and histopathological prognostic parameters. METHODS: Total S-100B (A1B + BB) and MIA concentrations were measured in the sera from 104 patients with uveal melanoma prior to enucleation and in the sera from 50 healthy controls. Concentrations were also determined in the sera from 30 patients with known uveal melanoma metastases. Liaison Sangtec 100, an automated immunoluminometric assay measuring the total S-100B, and Roche MIA ELISA were used to quantify these proteins in serum. Results were compared with liver function tests [alkaline phosphatase, lactate dehydrogenase (LD), aspartate aminotransferase, alanine aminotransferase and gamma-glutamyl transpeptidase]. RESULTS: The mean S-100B and MIA concentrations were significantly higher in patients with metastases compared to melanoma patients without metastases. At the time of enucleation, S-100B and MIA were not prognostic for metastases in uveal melanoma, but S-100B and LD were the best tests to predict the occurrence of metastatic disease during the follow-up period. CONCLUSIONS: In our study, the S-100B and MIA serum concentrations were not correlated with any tested established prognostic parameter. S-100B and LD showed better performance in identifying melanoma metastases than gamma-glutamyl transpeptidase and MIA. A prospective follow-up study is needed to evaluate S-100B and MIA in identifying early micrometastasis in uveal melanoma.